As outlined above, projects have different approaches to the sustainability they want to achieve, which will depend on the goals they set themselves. A project may focus on a single question they want to answer, or conduct their research continuously. In the former case, once such a question is answered, more questions might follow, which could become part of the project; or the project could use their results to achieve impact, but otherwise conclude. Projects that conduct continuous research may evolve over time, and adapt their questions, data collection and processing. They will have to develop appropriate models to sustain both their community, and their finances. 

With regards to sustainability, projects should consider three distinct aspects: Financial sustainability (i.e. continuous funding), output sustainability (i.e. keeping their results available for future use), and community sustainability. The community of a citizen science project are all the contributors who participate in it. It is important to support them to make it possible to maintain, or even to grow the project, and include a larger number of citizen scientists. 

What measures a project takes towards sustainability can look very different, depending on their setup and goals. Sometimes a project may not need further funding or to consider long-term sustainability. Citicomplastic wanted to understand the compostability of bioplastics – a closed question, which they answered in the negative. Negative findings in research are not a bad thing: In this case, they implied that the composting of bioplastics would require involvement by policy makers, which the team attempted through engaging relevant stakeholders directly. Conversely, De Vlinderstichting is a continuous project, which has evolved over time. Beginning from counts of butterflies, they later added dragonflies, and adapted their processes from paper forms, through an online portal, to an app for participants. The team spends considerable efforts on maintaining their community, through regular events, newsletters, and other engagement opportunities. All this is enabled through their direct work with the Dutch government, who funds their work.

Long-term sustainability may also be achieved through building connections and ensuring the continued use of project outputs. The Water Sentinels project works with a group of fisherwomen to educate them about water quality research, and thus enabling their community to advocate for themselves. Similarly, rather than expanding their own project, Open Soil Atlas have teamed up with similar communities in other cities, who want to replicate their effort. All citizen science projects should consider which sustainability measures are appropriate for them.

Community sustainability

Citizen science projects rely on contributions from volunteers, many of whom contribute sporadically or for only short periods of time. This means that attracting and maintaining the interest of a large number of volunteers is crucial to the success of a project. At the same time, it is important to note that many projects are at their most popular and attract the largest number of participants when first starting out. As time passes and volunteers leave the project, it becomes increasingly important to attract and recruit new volunteers. The question of community sustainability, then, is crucial.

Before considering community sustainability, however, it is important to consider three questions: 

  • How much data does the project need?
  • How quickly is that data needed?
  • How many volunteers are required to ensure all data can be gathered within that time-frame?

Volunteer turnover is an inevitable part of any citizen science project. Many volunteers will potentially contribute very little to a project before they leave. It is therefore essential to address this by recruiting many participants throughout the project life-span. 

Finally, and perhaps most importantly, projects only need to sustain their community for as long as they need this community. If a project is only intended to gather data to address a specific question, then when it has enough data, there is little need to sustain that community further. On the other hand, if it wishes to educate participants or carry out further research, then it should make sure that it is encouraging long-term participation, and that participants are aware of further opportunities to contribute and learn. If a project is part of a long-term goal, then it should recruit accordingly – grow the project early and frequently and maintain the participants’ interest. If a project is only short-term and can gather data quickly, then there may be less need for further recruitment, and it should consider only maintaining the initial community for long enough to complete those goals.

Financial sustainability

The majority of citizen science projects start out with financial support from small grants, mainly from public bodies, or are dependent upon goodwill, volunteering and pro bono work. However, these may not be sustainable, and financial sustainability is important for citizen science projects to run long term.

While costs at the beginning of a project may appear limited, projects should not underestimate the long-term requirements. Common costs projects need to cover include the purchase of hardware, such as sensors; communications costs; development or subscription fees for applications; staff costs, if not purely volunteer based; and infrastructure costs, for example to continue to run a website or database.

Becoming financially sustainable can be challenging for citizen science projects and for organisations that promote them. Depending on the project, there are various opportunities to ensure further funding or development of a business model to support a project. Care should be taken to ensure fairness in the commercialisation of any project that has relied on volunteer resources to develop. In practice, creativity is key to leveraging available opportunities. While the majority of environmentally focussed European citizen science projects rely on grant funding at initiation (Turbé et al., 2019), many projects rely on a portfolio of income streams and dynamic use of resources to maintain themselves (Cunha et al., 2017). 

Hardware sales

Where hardware has been developed within a project, even if designs or data are made open access, sales of kits or pre-built hardware can contribute to a project’s sustainability. Often this takes the form of consultancy on kit adaptation or improvement, training and similar. 

Subscription models

Often going hand-in-hand with Hardware Sales, citizen science projects, such as the Air Quality Egg, have developed subscription models to unlock software as a service, for instance providing access to App features or data processing tools. These models rely, however, on having some non-open code or data, requiring careful navigation in relation to the data guidelines discussed above.


Crowdfunding platforms have gained popularity in funding citizen science projects since the early 2000s. Now used by both academic institutions and for bottom-up citizen science projects to gain funding, successful projects have a clearly defined goal and offer unique opportunities to their funders. Design and promotion of a crowdfunding campaign requires time and thought, and for content to be tailored to a particular audience. While a single crowdfunding instance does not deliver financial sustainability for a project – and can risk a high administrative overhead – this option can form part of a portfolio approach to maintaining a project long-term. 

Up-scaling funding applications

Once a project has been running for a little while, generated results and demonsted impact, there is a stronger case to be made in applying for larger funding opportunities at a national and international level. Key factors that affect the strength of a follow-up funding case are: proven impact, strong dissemination, strong network (including international partner organisations if appropriate) and a strong argument for growing the project (either in terms of size, geographical reach, extending the approach to a new problem space…)

Direct donations

Projects with a strong cause-oriented or community dimension may be able to raise funds through direct donations. In this case, and in particular if running a donation drive, it is good practice to make the possibility of donating clear in publications (press releases, website, social media), and to put technological solutions in place to facilitate a smooth process of enacting the donation, such as a paypal donate button on the projects’ web page. Communication materials should focus on the impact of the project on the key topic of interest of the community.

Reframing as science education

In strategies similar to those employed by science, citizen science projects can access new funding opportunities by (re-)framing their work as informal science education (Ottinger, 2017). This opens another stream of local, national and international funding and asks citizen science managers to streamline their approach in order to be scalable and applicable to different learning communities and settings. This approach may be particularly suitable for educational projects.

Private funding within the Corporate Social Responsibility framework

Large and medium sized enterprises support, as part of their Corporate Social Responsibility (CSR) plans, local initiatives that tackle topics close to the company focus or that are of special relevance for their managers and employees. This can be another channel for obtaining financial support for specific citizen science projects. In order to be successful when following this sustainability path it is important to get in touch with the potential funders directly by contacting the CSR manager with a short and to the point message that describes the project and its positive impacts. The selection of the companies to be contacted should be based mainly on two criteria: location and closeness to the projects’ topic. In other terms, companies are interested in local impacts and prefer to support initiatives that have operated in the territory they operate with. At the same time, they tend to prefer initiatives that are somehow related to the topic or sector they operate in. For example, a sportswear company can be interested in citizen science projects that engage volunteers in outdoor measurement activities in nature. This potential stream of funding is more easy to pursue for projects that can count on a large community of volunteers and that can assure a good visibility to the funder.


Guidelines for financial sustainability

Community Funded guidelines

Community Funded is a crowdsourcing platform supporting research and non-profits. Both the platform and their guidelines can be useful for citizen science projects considering funding their projects through community contributions.

Crowdfunding platforms

Popular platforms for citizen science projects are and, Goteo and The latter was specifically designed for science projects, and vets the projects for minimum scientific rigour before publication.

ACTION Webinar on financial sustainability

In this webinar, supported by several experts, we present different complementary paths towards sustainability, including many discussed above, and practical examples.



Stars4all was a project dedicated to light pollution, funded by the European Commissions’ seventh framework programme. In order to assure sustainability of the project and its community, a not-for-profit, public interest foundation was established in Spain. The selection of this legal entity was driven by several considerations, such as the options to collect donations from private citizens and organisations, and to participate in public open calls. The Stars4all foundation sells photometers: a device developed during the initial project, which allows citizens to measure light pollution. The foundation is responsible for the manufacturing, sales and post-sale support. It has a marketplace where people can buy merchandise, and provides open data management support. It also supports CS projects in carrying out crowdfunding campaigns, and organises awareness raising events.