Recent directions in organizational studies have demonstrated progressive social movements' ability to generate rewarding enterprises or environmental opportunity structures (EOS) in receptive markets. However, more nuanced opposing movements (Meyer and Staggenborg 1996), such as the pro-choice and pro-life movements, receive far less attention, leaving scholars to postulate that there is much yet to know about the impact of movements other than those with strict progressive orientations (Zald, Morrill, and Rao 2005). To better understand how opposing movements contribute to environmental opportunity structures, this thesis examines dramatic growth in the number of adoption agencies advertising services in the Yellow Pages during the last quarter of the twentieth century. Some suggest the growth may be due to changing attitudes and laws regulating interracial adoption, the growing acceptance of international adoption as a family formation strategy, and the success of the adoptee rights movement. However, I argue that at least some of this growth is related to changes in abortion laws associated with the Roe v. Wade Supreme Court decision and associated pro-choice and pro-life opposing movements that dominated public debate during the same period. Applying cultural entrepreneurship and competitive framing, I demonstrate that pro-choice language is adopted by adoption agencies that compete with abortion clinics as they offer services to birth mothers. Opposing movement features are evident in organization growth patterns, the services offered, and the slogans used. Dissecting the adoption services field into generalist and specialist organizational forms, I find that specialists experienced precipitous growth and were more likely to make use of certain "choice" frames, co-opted from the pro-choice movement and redirected to support pro-life ideologies. Further, I find that "open adoption" services, championed by the adoptee advocacy community for their identity-affirming and sustained relationship-allowing practices, are most often marketed by the adoption provider as a choice-granting process, giving adoption providers further opportunity to mirror the pro-choice movement's choice-centric practices. Because adoption agencies' growth, slogans, and services are largely bound up in tactics specific to the pro-choice and pro-life opposing movement dynamics, I conclude that opposing movements can indeed contribute to environmental opportunity structures for market growth.