This aim of this research project is to determine if low to moderate level exercise can have an impact on stress, fatigue, and quality of life for individuals diagnosed with a primary immunodeficiency disease. This 8-week study will compare participants engaging in a semi-customized, home exercise program (exercise intervention group) to participants performing normal activities (non-exercise control group). This study will track stress, fatigue, and quality of life in individuals with a diagnosis of primary immunodeficiency disease, using standardized questionnaires, journals, and interviews.