Although the stressful nature of high risk exposure software projects and the adverse repercussions of stress on project participants and performance have long been recognized, there is still little research on the subject. This paper builds upon two foundations - the cognitive-transactional theory of stress and the concept of software project risk exposure - to propose a model of software project risk drivers as software project manager stressors and coping resources. The model posits that some software project risk drivers - core project characteristics and project objectives - play the role of stressors and that other risk drivers - project environment characteristics - play the role of coping resources. The model further suggests that software project managers are faced with both chronic stress and acute stress, which have different antecedents. This paper broadens current understanding of the role of software project risk drivers; it also contributes to knowledge on software project management by focusing on the emotional components this activity.