The effects of two dimensions of job insecurity (job loss insecurity and career insecurity) on turnover intentions were tested in a sample from the Dutch armed forces (N = 3,580) after a major downsizing operation was announced. Results suggested that especially perceptions of career insecurity increased turnover intentions. Next to this direct effect, career insecurity was also associated with lowered affective organizational commitment which in turn increased turnover intentions as well. Our results imply that, at least during downsizing operations, a multidimensional conceptualization of job insecurity helps to predict important organizational outcomes in the military. Both perceptions of the risk of losing one’s job and perceptions of possible future career opportunities are important for employee retention.