Change over time is also evident in the internal structure and dynamics of the family. This is seen when comparing the findings of two classical anthropological studies of the rural Irish family. The first of these studies was carried out by Conrad Arensberg and Solon Kimball (1940) in the 1930s. This study showed that there was a single family type in rural Ireland that was characterized as having a dominant patriarchal authority system with a rigidly defined division of labor based on gender. In contrast, the second study carried out by Damian Hannan and Louise Katsiaouni (1977) in the 1970s, when the process of change had begun, found a wide variety among farm families, including the socialization experiences of spouses and family interaction patterns. They also found that families were more democratic in structure and that there was a move towards a division of labor based on competence rather than gender. The authors concluded that the family was going through a process of change from a traditional to a modern form, and they linked these changes to the changes taking place in the economic, social, and cultural environments in Ireland at the time.
Changes in the family are also associated with the decline in the influence of the Catholic Church on Irish family life, especially in the area of sexual morality. The traditional family in Ireland has long been characterized as highly conservative, reflecting the dominant value system of the Catholic Church. Although religious practice continues to be high, evidence shows that the influence of Catholic teaching on family life has greatly diminished. This is seen, for example, with the widespread use of contraception and the extent of sexual activity outside marriage. These behavioral changes were also accompanied by the introduction of extensive new legislation on family matters in the 1980s and 1990s, including the passage of a referendum on divorce that led to the introduction of no-fault divorce. Much of this legislation challenged the traditional ideology of the Catholic Church that promoted the privatization of the family and was strongly opposed to state "interference" in family matters.