This paper reports and extends discussions carried out during a workshop held at the Santa Fe Institute in August 1995 by the authors. It treats eight major topics: (i) the importance of carefully examining research on routine, (ii) the concept of 'action patterns' in general and in terms of routine, (iii) the useful categorization of routines and other recurring patterns, (iv) the research implications of recent cognitive results, (v) the relation of evolution to action patterns, (vi) the contributions of simulation modeling for theory in this area, (vii) examples of various approaches to empirical research that reveal key problems, and (viii) a possible definition of 'routine'. An extended appendix by Massimo Egidi provides a lexicon of synonyms and opposites covering use of the word 'routine' in such areas as economics, organization theory and artificial intelligence. Coauthors are Roger Burkhart, Giovanni Dosi, Massimo Egidi, Suigi Marengo, Massimo Warglien, and Sidney Winter. Copyright 1996 by Oxford University Press.