Content trends were analyzed in more than 3,000 articles in two selected special interest magazines ("Audubon" and "Environment") and two general audience magazines ("Time" and "Saturday Review") for the period 1959-1979. Through this analysis, the study examined the role of the two media types as well as the communication process involved in the crystallization and diffusion of the environmentalist movement and the unification of its substantive concerns. For the special interest magazines, a single issue was randomly sampled for each of the years of the study period. For the general audience magazines, one weekly issue was then randomly sampled from the 8-week period corresponding to the already sampled issue of the special interest magazines. Each article was coded, and individual articles served as the unit of analysis. A total of 1,182 articles from special interest and 1,802 articles from general audience magazines were coded. Content variables were defined at three levels of abstraction: general, relevant, yet essentially unfocused environmental content; doctrinal ideology marked by the themes of fragility, diversity, quality, and policy; and comprehensiveness. Data revealed that early sustained attention by special interest magazines preceded attention in general magazines. It was determined that interest in environmental concerns followed a cyclical pattern that had little relation to real events in history, and that the movement went from crusade to popular movement to its current managerial/bureaucratic status. (CRH)