PIP: This work discusses methodological aspects of the articulation and evaluation of behavioral theories underlying demographic policies. Such theories, called "policy theories" among other terms, may be defined as a group of hypotheses explicitly translated into predictions about behavior that underlie policy measures and that concern the relations between the measure and the objective to be attained. Interest in policy theories has been reflected in the writings of such demographers as D. Bogue, J. Blake, and T. Burch, and of researchers from other social science disciplines. 2 examples of policy theories from the Netherlands are presented to illustrate the discussion, 1 describing family planning communication programs that were intended to reduce the number of unwanted and unplanned pregnancies, and the other describing measures to increase availability of child care services in order to facilitate labor force participation of women and ultimately to increase the birth rate. Both theories are found to be comprised of 2 main parallel theories and several related hypotheses. Because political authorities do not usually make explicit the hypotheses that support political measures, their hypotheses must be articulated and reconstituted through attention to debates, written communications, interviews, and other means. The reconstitution must be done as objectively as possible, which implies the need to follow some methodologic rules. Examples are cited of principles advanced by researchers in management science, market research, and political science. 7 methodological rules or steps are then suggested for articulating policy theories: 1) identify statements relative to the political problem, such as excessive or inadequate fertility rates; 2) use the sources to identify reasons for undertaking concrete policy measures; 3) describe the role of the official in the political process; 4) inventory all declarations concerning the relationship between the objective and the means of attaining it; 5) make explicit the links and sequences left implicit in these declarations; 6) identify the normative declarations relative to the policy problem under study, and 7) try to classify all the inventoried declarations into "if-then" or "more-more" statements in a system of hypotheses where each hypothesis can be deduced from another hypothesis. Evaluation of policy theories is necessary and can be conducted according to epistemological criteria as well as criteria relating to implementation and strategy.