This article addresses teachers' use of their professional time. With the support of substantive grounded theories from two separate studies--focusing on two "invisible" parts of teachers' work: recesses and off-the-clock work--we aim to conceptualize some patterns in contemporary work of teachers and discuss them in the light of changing working conditions in a time of insecurity. Our findings indicate differences in how teachers handle a work environment characterized by uncertainty and provide an elaborated explanation of how recent changes in working conditions have affected teachers' apprehension and work performance. The discussion points to novel means to understand and re-frame reasonable and sustainable working conditions for teachers. (Contains 3 figures and 1 note.)