This thesis examines the underlying health impairment and motivational processes associated with volunteer retention, commitment and satisfaction within the Special Constabulary. Recognising the need to understand the impact of organisational-type variables on the volunteer experience, as well as the unique occupational hazards associated with police work, a theoretical model of volunteer retention within the Special Constabulary is developed based on the framework provided by the Job Demands-Resources (JD-R) model. An online survey was distributed to volunteers serving at two Special Constabularies (N=272), with a follow-up survey sent out 6 months later (N=150). Secondary data analysis of volunteer workforce management data was also conducted to further understand the impact of operational duties on well-being and retention. Strong support for the effect of various job characteristics within the health impairment and motivational pathways was found. Longitudinal analysis also confirmed the existence of causal and reciprocal relationships between burnout, connectedness and outcome measures. The effects of burnout highlight the detrimental ways in which the demands of police work lead to the development of distancing behaviours. Burnout may therefore also have implications for the conceptual relationship between the Special Constabulary and the public. Volunteer work can however be motivational and offset the experience of burnout. Connectedness was influenced by organisational support and training, as well as on-the-job learning and the provision of challenging assignments. Importantly these findings suggest that rather than simply benefiting from the development of a favourable working environment, volunteers are also motivated to continue in their roles by the provision of job challenge. Overall these findings highlight the importance of job design in volunteerism. Providing volunteers with support, training and job challenge, whilst ensuring specials know what is expected of them and facilitating stronger working relationships with regular police officers has positive effect on retention.