How can research contribute more directly to promoting and leading to sustainable solutions and projects? This article suggests that one of the most important research approaches capable of achieving this is the Action Research approach. This involves the researcher taking on a number of roles when working with other actors (e.g. citizens, farmers, local elected officials, citizen associations, government representatives. . . with the specific set of actors depending upon the nature of the subject being investigated and for which solutions are sought). The roles that the researcher can play involve providing appropriate information to the other actors, providing counseling to them, organizing and animating meetings with the actors, and accompanying the whole process involving all the... actors. These roles are essentially played out by the researcher when the other actors request the researcher to assume whichever roles they consider to be significant. The fundamental notion is that through this process the actors appropriate the sustainable solutions as their own, and the researcher helps them achieve this. This article is based on: a) a synthesis of pertinent research using the Action Research approach (specifically in relation to sustainable agricultural systems in periurban territories), and b) specific research undertaken by the two co-authors of the article, all in the context of periurban agricultural systems during the last 8 years, as well as on some of their publications. The necessary characteristics of Action Research and the researchers involved are identified, namely: a) patience; b) an emphasis on process; and c) an emphasis on participation on the part of multiple actors.