This issue of New Directions for Evaluation (NDE) marks a milestone: the 25th anniversary of the American Evaluation Association (AEA). NDE is an official publication of AEA and has been a crucial means for the Association to foster and promote the professionalization of evaluation through thematic discussions of theory and practice in evaluation. NDE was first published in 1978 under the name New Directions for Program Evaluation, although the title became New Directions for Evaluation in 1995 in acknowledgement of the broader scope of evaluation.