collaborative
adjective /kəˈlæbərətɪv/
  /kəˈlæbəreɪtɪv/
 [only before noun] (formal)- involving, or done by, several people or groups of people working together
- collaborative projects/studies/research
 - a collaborative effort/venture
 
Oxford Collocations DictionaryCollaborative is used with these nouns:- effort
 - endeavour
 - enterprise
 - …