Ninety-five teachers in Key Stage 1 in England and Wales completed a questionnaire and records of time spent on work over a period of 14 consecutive days, resulting in detailed records of 1,330 days of teachers' time. The data are analyzed in terms of overall time spent on work; time distribution; and time spent specifically on teaching, preparation, administration, inservice training, and other activities. The range of time spent overall was considerable, with the lowest being equivalent to a working week of over 38 hours and the highest being equivalent to nearly 73 hours a week. The average was 49 hours 35 minutes. Overall, teachers spent 35 percent of their time teaching, 31 percent in preparation, 29 percent in administrative activities, 18 percent in inservice training, and 6 percent in other activities. Implications for education policy are discussed, focusing on conditions of work and activity-led staffing, the delivery of the national curriculum, the use of teachers' time, and issues in conceptualizing teacher time at work. Appendices contain the form used for recording teacher time, a copy of the time survey questionnaire, and statistical data from the study. (JDD)