This first paper in the intrapersonal skills series presents a conceptual model of intrapersonal skills. Intrapersonal skills are defined as those skills individuals need to possess and perfect in order to manage themselves, and as a prerequisite to interpersonal skills. It is noted that intrapersonal skills are concerned with lessening internal conflict; understanding how one handles perceived external experience internally; and coming to terms with one's qualities, limitations, and potential. The conceptual model presented here views people as systems with inputs, processes, outputs, and, as open systems, with a feedback loop between output and input. Two systems models, a simple, closed physiological model and a more complicated, open psychological one, are illustrated and discussed. The psychological system is then expanded to include needs, decisions, and goals in the model. The effects of natural limitations, value added limitations, and cost/rewards analysis on the model are considered. A flow chart of intrapersonal conflict is provided and five defense mechanism responses to conflict are discussed: (1) reaction formation; (2) displacement; (3) projection; (4) introjection; and (5) rationalization. (NRB)