November 2010. "Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Occupational Therapy Department, College of Allied Health and Nursing, Nova Southeastern University." This study explored the lived experiences of older mothers who continue to be the primary care providers for their adult children who have intellectual disabilities. This research study used the Person-Occupation-Environment model (Law et al., 1996) from occupational therapy and occupational science as the orienting framework. The broad question this study sought to answer was: What are the lived experiences of perpetual mothers who live with their adult child with intellectual disabilities? Other related questions were: How have mothers created and adapted daily routines and occupations for themselves and their children? What meaning and purpose evolves for perpetual mothers from their lifelong caregiver role? How do they describe this sense of meaning and purpose? The grounding of this study within occupational therapy and occupational science combined with the research questions led to implementation of a phenomenological research approach for this research. Specifically, the structure inherent in Interpretative Phenomenological Analysis (Smith, Larkin, & Flowers, 2009) was adopted as the guide to methodology. Participants were identified using purposive and snowball sampling and were interviewed using Seidman's (2006) three-interview structure. The five women who participated in this study ranged from 68 to 83 years old. The themes that emerged represent structures that articulate the core of their lived experiences as primary caregiving mothers of adults who have intellectual disabilities. The essential structures or themes of these women's lived experiences are mothers' actions to structure daily life for their sons, mothers' routines--engaged lives, mothers' expertise, and mothers' reflections on mothering a son with intellectual disabilities. The results of this study contribute a focus on maternal experiences to the body of literature about, and practice with, adults who have intellectual disabilities and their families. In addition, this study contributes to the body of literature about mothering occupations found in occupational therapy and occupational science. This dissertation discussed implications for occupational therapy practice and research.