In short
ISO 20121 is a management system standard for event sustainability, not a checklist: it covers environmental, social and economic impacts, and the current edition is ISO 20121:2024.
It is the organisation that is certified, not the event: agencies, venues and suppliers define a scope that can cover all their activity or a single major event.
In Italian public procurement, the CAM for events are mandatory under Article 57 of Legislative Decree 36/2023 and award a higher score to ISO 20121 than to ISO 14001 or EMAS.
ISO 20121 and ISO 14001 share the harmonized structure: you can integrate them into a single system without duplicating documents, audits and reviews.
The auditor wants to see the system in action: supplier criteria, data collected during events and evidence from at least one event managed under the new rules.
Clients and public buyers are asking for sustainable events, but "green" is no longer enough: you need a system. ISO 20121 is the international standard designed for agencies, venues and organisers who want to show, with clear and verifiable rules, how they manage the environmental, social and economic impacts of their events.
More and more often, an agency bidding for a conference contract, or a venue pitching for a festival, is asked very specific questions: how do you manage waste, what does the catering serve, how do attendees get there, who checks the suppliers, how do you measure results. In this guide we look at what ISO 20121 is and what it is not, who it applies to, why it matters in public procurement under the Italian Minimum Environmental Criteria for events, what it requires in practice, how it integrates with ISO 14001 and how certification works. If you are new to ISO standards, you may want to start with our guide on what ISO certifications are.
What is ISO 20121, and what is it not?
ISO 20121 is the international standard that specifies the requirements for an event sustainability management system. Its official title is "Event sustainability management systems — Requirements with guidance for use": it therefore contains certifiable requirements together with guidance on how to apply them. The current edition is ISO 20121:2024, which replaced the first edition of 2012; in Italy it is published by UNI as UNI ISO 20121:2024.
The standard works across three dimensions of sustainability: environmental, social and economic. So it does not stop at waste and energy, but also covers accessibility, inclusion, working conditions, the impact on the local area and the responsible use of financial resources. The 2024 edition strengthened the social aspects in particular, such as the legacy an event leaves to the host community and inclusivity.
A management system, not a checklist
The ISO technical committee responsible for the standard states it explicitly: ISO 20121 is not a checklist, not a reporting framework and not a method for scoring the sustainability of an event. It is a management system, that is, an organised way of deciding, planning, controlling and improving.
In practice, the standard does not tell you "use only reusable cups" or "serve only locally sourced food". It asks you to understand the significant impacts of your events, set objectives, assign responsibilities, involve suppliers, measure results and learn from each edition. The concrete choices are yours, based on the type of event, the location and the expectations of interested parties.
An event is not sustainable "in absolute terms"
A key idea of the standard is that sustainability is not a label you attach to a finished event. Presenting the Italian edition, UNI points out that an event is not sustainable in absolute terms but managed in a sustainable way. The difference is substantial.
A concert with tens of thousands of spectators will always have an impact: transport, energy, waste, noise. The right question is not "is it green?" but "has the organiser identified the main impacts, made consistent decisions, had suppliers comply with them and can they prove what was achieved?". It is this management capability that certification verifies.
Who does ISO 20121 apply to: agencies, venues and suppliers?
ISO 20121 applies to organisations of all types and sizes involved in the design and delivery of events. The entity that adopts the system and is certified is therefore the organisation, not the event itself: the certificate attests that the company manages its events, or its part of an event, in line with the requirements of the standard.
When the first edition was launched, ISO already explained that the standard concerns the whole supply chain: organisers, event managers, stand builders, caterers, logistics suppliers.
The certificate belongs to the organisation, the scope is yours to define
Every management system has a scope, that is, the boundary of activities, sites and events it covers. In ISO 20121 the boundary can be drawn in different ways. An agency can include all its event design and organisation work for clients. An organising committee can limit it to a single major event: the first edition of the standard, ISO notes, was applied to the London 2012 Olympic and Paralympic Games.
The scope needs to be chosen carefully. A scope that is too narrow, for example one event a year when you organise thirty, produces a certificate that tells clients little and may not count in tenders. One that is too broad, at the start, can make the system heavy to launch.
Three typical profiles in the supply chain
An events and conference agency controls almost every lever: it chooses the venue, plans the logistics, selects caterers and stand builders, handles communication. For an agency, ISO 20121 is the way to turn client requests into a repeatable method and to approach tenders with concrete evidence.
A venue or conference centre, on the other hand, manages the infrastructure: energy, water, waste, accessibility, nearby public transport, in-house services. For a venue, the standard shows organisers that the site is an ally, not a problem, when they have to meet sustainability requirements.
Supply chain businesses such as stand builders, audio and lighting providers, caterers and rental companies are increasingly asked to demonstrate their performance to those who hire them. ISO 20121 in fact asks those who adopt it to extend their influence along the supply chain.
Why "green" is no longer enough: clients, tenders and the CAM for events
"Green" is no longer enough because public and private buyers ask for measurable, documented requirements, not statements. In the Italian public sector this demand has a precise legal basis: the Minimum Environmental Criteria (CAM) for the service of organising and delivering events.
What the CAM for events are
The CAM for events were adopted by the Italian Ministry of the Environment with Ministerial Decree no. 459 of 19 October 2022, published in the Official Journal no. 282 of 2 December 2022, and are listed among the CAM in force of the Ministry of the Environment and Energy Security. By way of example, they apply to cultural events, artistic events, historical re-enactments, food and wine events, festivals, exhibitions, sporting events, conventions, conferences, seminars and trade fairs.
The document covers the entire event cycle, from organisation to post-event. The contract clauses include the appointment of a Sustainability Manager, materials and tickets preferably digital and accessible, reusable set-ups, waste management agreed with the local operator, tap water, measures against food waste, sustainable mobility, staff training, worker protection and accessibility for all attendees.
Public procurement: what the Public Contracts Code says
The Italian Public Contracts Code, Legislative Decree no. 36 of 31 March 2023, in Article 57(2), requires contracting authorities to include in tender documents at least the technical specifications and contract clauses of the CAM. The Ministry specifies that the obligation applies to the full value of the tender and that the CAM must also be taken into account when setting the award criteria.
If you work with public bodies, this means something concrete: the clauses of the CAM for events become contractual obligations that you must meet and document during performance. The contract performance manager can check compliance with the criteria through site inspections and by requesting the required documentation.
Where ISO 20121 counts in a tender
The CAM for events refer to ISO 20121 explicitly. Among the award criteria, which the contracting authority uses when awarding on the best price-quality ratio, is the adoption of an environmental or event sustainability management system. The text provides points for EMAS registration or ISO 14001 certification in the relevant sectors, and a higher score for ISO 20121 certification issued by an accredited body.
ISO 20121 also appears in the award criterion on monitoring environmental performance, intended for large or recurring events: holding the certification is indicated as one of the ways to demonstrate it. The CAM, adopted in 2022, cite the edition of the standard in force at the time: when you read a tender notice, check which edition it refers to and how the contracting authority asks you to demonstrate it.
What does ISO 20121 require in practice?
ISO 20121 asks you to manage event sustainability with the same cycle as other management system standards: understand the context, plan, implement, check, improve. The full text is sold by ISO and we do not quote clause numbers, but the building blocks are clear.
Context, interested parties and scope
The starting point is to understand who is involved and what they expect: clients, commissioning bodies, attendees, suppliers, sponsors, the local community, public authorities that issue permits.
The scope is drawn from this analysis and must be written down clearly. If you want to go deeper into how to analyse interested parties, we cover it in our guide on the ISO 14001 environmental management system, where the method is the same.
Policy, significant issues and objectives
Top management sets a sustainable development policy for events and identifies the significant issues: energy, waste, transport, food, accessibility, working conditions, impact on the local area. Each issue needs measurable objectives and a plan to achieve them.
A useful objective is concrete and verifiable. "Reduce plastic" is not; "eliminate single-use bottles in the catering areas of all conferences, using tap-water dispensers" is.
Suppliers and operational changes
Much of an event's impact depends on who actually delivers it: stand builders, caterers, transport, the venue. The standard asks you to bring sustainability requirements into the selection and control of suppliers, with criteria written into contracts and checks during the event.
Events often change at the last minute: the venue changes, the number of attendees doubles, a supplier pulls out. A well-designed system sets out how to assess these changes, so that decisions taken under pressure do not cancel the commitments made to the client.
Monitoring, internal audit and review
After each event you need data: consumption, waste by fraction, attendance, how attendees arrived, complaints, supplier nonconformities. The data feed into the management review, which decides what to improve for the next edition or the next event.
The internal audit checks that the system really works, not just on paper. If you follow the path with Complaion, you carry out the internal audit with us: it is conducted by the Complaion Lead Auditor, who verifies the system independently without checking their own operational work. You will find the full method in our guide on ISO internal audits.
A practical example: a conference for a public body
Imagine a 25-person agency that organises scientific conferences and bids in a public body's tender for a three-day convention. The tender notice refers to the CAM for events and, among the award criteria, gives points for ISO 20121 certification.
Without a system, the agency prepares its bid by gathering information at the last minute: it asks the caterer whether it has reusable plates, the venue whether it can provide consumption data, the transport company what vehicles it uses. During the event nobody collects evidence in an orderly way and, at the end of the contract, the sustainability report is written from memory.
With an ISO 20121 system, the same tender is handled differently. The Sustainability Manager is already appointed, qualified suppliers have already signed up to the requirements, the data collection templates are ready. The table shows how some typical CAM requests are answered by the system.
Typical CAM request | How an ISO 20121 system handles it | Evidence to keep |
|---|---|---|
Sustainability Manager | Roles and responsibilities set by top management | Appointment signed by the legal representative |
Waste management with the local operator | Waste objective and operating procedure for each event | Agreement with the operator, data by fraction after the event |
Catering without single-use items and against food waste | Requirements in supplier contracts and on-site checks | Contract, photos and site inspection records |
Staff training | Training and awareness programme | Programme, attendance register, materials |
Monitoring environmental performance | Indicators, data collection and review after each event | Report with indicators and improvement actions |
ISO 20121 and ISO 14001: how do they integrate?
ISO 20121 and ISO 14001 integrate well because they share the same basic structure. ISO rules require new or revised management system standards to follow the harmonized structure: the same main clauses, the same core terms, the same logic of context, leadership, planning, support, operation, performance evaluation and improvement.
The difference lies in the boundary. ISO 14001 covers the environmental management of the whole organisation: sites, processes, environmental aspects, compliance obligations. ISO 20121 focuses on events and adds the social and economic dimensions: accessibility, inclusion, working conditions, legacy for the local area.
When it makes sense to have both
For a venue or conference centre, ISO 14001 makes a lot of sense: it manages a building with energy consumption, installations, waste and ongoing environmental obligations. If the same venue also organises its own events, ISO 20121 adds the management of the event as a whole.
For an agency without significant premises of its own, ISO 20121 is often the most direct choice, because it speaks the language of clients and sector tenders. Some buyers, however, require ISO 14001 as a general supplier requirement: in that case an integrated system avoids duplicating documents, internal audits and reviews.
How to avoid two parallel systems
The mistake to avoid is building two separate systems with two policies, two risk registers and two audit programmes. With the harmonized structure you can have a single context, a single analysis of interested parties, a single management review, and manage both environmental aspects and event sustainability issues in the same register. We cover this in our guide on the integrated management system.
How does ISO 20121 certification work?
Conformity with ISO 20121 can be demonstrated in three ways: by self-declaration, by verification from an interested party such as a client, or through third-party certification issued by an independent body. In public tenders, when the CAM reward ISO 20121, the certificate issued by an accredited body is required.
The certification path follows the scheme common to management systems: a first documentary and readiness audit, a second on-site audit to verify that the system is implemented, then periodic surveillance audits and renewal at the end of the three-year cycle. With ISO 20121 the auditor will want to see the system in action, so it makes sense for the path to include at least one event managed under the new rules. The two stages of the initial audit are explained in our guide on stage 1 and stage 2.
What must be ready before the audit
Before the certification audit, the essential elements must be in place: scope, policy, analysis of interested parties, significant issues and objectives, supplier criteria, operating procedures for events, monitoring data, internal audit and management review. Evidence from at least one event is what makes the system credible.
If you are already certified to the previous edition of the standard, ask your certification body how and when the transition to the current edition will take place, and check what changes for your system, starting with social aspects and the supply chain.
What Complaion does on an ISO 20121 path
On a path with Complaion, a dedicated Lead Auditor supports your organisation from defining the scope to the certification audit: they help you identify the significant issues for your events, set measurable objectives, translate CAM requirements into supplier criteria, and they conduct the internal audit. The platform collects the evidence from each event (waste and consumption data, site inspection records, supplier contracts, training records), manages documents with up-to-date versions and keeps the schedule of audits, reviews and renewals. You will find the details on the ISO 20121 certification service page.
What are the most common mistakes?
The most frequent mistake is confusing ISO 20121 with a list of good practices. Compostable cups and electric shuttles are fine, but without context analysis, objectives and measurement there is no system, and the auditor notices at the very first audit.
The second mistake is leaving suppliers out. If the caterer uses single-use items or the stand builder throws everything away at the end of the fair, the organiser's commitments remain on paper. Requirements must be written into contracts and checked during the event, with evidence.
The third mistake is not collecting data during the event. After dismantling it is almost impossible to reconstruct how much waste was produced, how attendees arrived or how much energy was used. Prepare forms and responsibilities before the event, not after.
The fourth mistake is communicating more than you can prove. Calling an event "zero impact" or "fully sustainable" exposes you to challenges. The standard goes the opposite way: communicate accurately, with verifiable data and stated limits.
How to simplify the path with Complaion
An ISO 20121 system that works lets you answer tenders with evidence, talk to clients with real data and improve event after event. Complaion helps you build it without weighing down an organisation that lives on deadlines and set-ups. We start from your needs and propose the path that suits you best: ISO 20121 on its own, a system integrated with ISO 14001, or a path that starts from the requirements of the CAM for events. A dedicated Lead Auditor supports you at every stage, while the platform collects the evidence, manages documents, keeps the schedule and prepares the audit. The path with Complaion helps you avoid nonconformities and leads to the external audit with a 100% success rate: it is the method with which we have already supported more than 1,000 clients. The cost depends on size, number and type of events, sites and starting point: contact us for an initial assessment and a tailored quote.
Frequently asked questions about ISO 20121
What is ISO 20121 in simple terms?
It is the international standard that sets out how to manage an events organisation sustainably from an environmental, social and economic point of view. It does not list mandatory solutions, but asks you to identify significant impacts, set objectives, involve suppliers, measure results and improve over time. It can be certified by an independent body. The current edition is ISO 20121:2024.
Is the event or the organisation certified?
What is certified is the organisation's management system. The certificate states a scope, which may cover all the activity of an agency or a venue, or a single major event run by an organising committee. In every case the auditor checks how the organisation plans, delivers and controls the events within the boundary. That is why it is important to define the scope consistently with what you actually do.
Is ISO 20121 mandatory for public tenders?
No, certification is voluntary. In tenders for events, however, contracting authorities must include the technical specifications and contract clauses of the CAM for events, as required by Article 57 of Legislative Decree 36/2023. ISO 20121 certification is among the CAM award criteria and can earn you a higher score than other management systems. Always check in each tender notice which criteria have been included.
What are the CAM for events?
They are the Italian Minimum Environmental Criteria for the service of organising and delivering events, adopted by Ministerial Decree no. 459 of 19 October 2022 of the Ministry of the Environment. They set contract clauses and award criteria on topics such as waste, catering, mobility, energy, set-ups, accessibility, training and worker protection. They apply to events awarded through public procedures: conventions, trade fairs, festivals, exhibitions, sporting and cultural events.
What is the difference between ISO 20121 and ISO 14001?
ISO 14001 covers the environmental management of the whole organisation, including permanent sites and processes. ISO 20121 focuses on events and also considers social and economic aspects, such as accessibility, inclusion and impact on the local area. They share the same basic structure, so they can be integrated into a single system. The choice depends on what your clients ask for and how much your premises weigh.
Can a venue be certified to ISO 20121?
Yes, the standard applies to all organisations involved in the design and delivery of events, including venues and conference centres. For a venue the system mainly concerns infrastructure and services: energy, water, waste, accessibility, transport and in-house suppliers. A venue may also consider ISO 14001, because it manages a building with ongoing environmental aspects. An integrated system avoids duplicating work.
How much does ISO 20121 certification cost?
There is no standard cost, because it depends on several factors. What matters is the size of the organisation, the number and type of events within the scope, the sites involved and how structured you already are. The choice between an ISO 20121-only system and a system integrated with ISO 14001 also plays a part. The most reliable way to find out is to start with an initial assessment and ask for a quote.
