The cooperation project should have clear objectives for all involved, and they should be made known.

You never do a project just for the sake of doing it. What the aims and objectives of your project are should be clear from the very beginning. All those involved, including the volunteers and participants, should know them.

Make sure the objectives are SMART (Specific, Measurable, Achievable, Relevant, and Time-Bound).

Check out this video to find out more about SMART Objectives (English with subtitles in eight languages): 
Roskilde Festival has made good experiences using another approach, called OKR – Objectives and Key Results. Find out how it works in this article:

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