Two case studies are presented to compare and contrast the challenges encountered when attempting to conduct participatory evaluations (P-Es) with tribal programs that represented two extremes of collaboration between the programs and evaluators. In one case, the P-E was successful because the principals were invested in the program, whereas in the second case, the absence of a shared program vision hampered the ability to adequately evaluate the program. The authors contend that governmental funding agencies have responsibilities to ensure that their expectations are appropriate, the proposed program is feasible, and that technical assistance should be provided before the grant is written, not after it has been funded. (Contains 3 notes.)