The issue of global population development and the associated problems and topics, such as family planning, has occupied the leadership of the Roman Catholic Church (When we talk about “Church” in what follows, we are referring to the Roman Catholic Church) for many decades. However, it is clear that, at least within the Church, the initially broad view of the topic has been focused on the moral judgment of methods of birth control and conception regulation, so that many other pressing problems have been ignored or marginalized. Today, it is important to look at the topic in all its complexity and range of ethical aspects. This will be demonstrated in this chapter, which is divided into three sections. After a short clarification of the terminology, the first section will trace the development of Catholic teaching on regulation of birth and family planning since the 1960s. From the outset, it will become evident that the Catholic position is complex and nuanced, certainly not as straightforward as commonly assumed. The second section will present moral criteria for contraception methods and family planning. This section aims to encourage an open, critical, and constructive dialogue. The third section will reflect on family planning and population growth in the context of the present eco-social crisis. Finally, the comments will be summarized in six theses.