This study explored the extent to which teachers' participation in leadership and decision making affects their teaching practices, particularly their planning and delivering of instruction. The study involved an open-ended survey of 25 teacher leaders in a school district in central Texas, which was a school-based management site that had incorporated a Peer Assisted Leadership and Support component. Findings are presented according to the following themes: time frame of performance, need for leadership preparation, effect of teacher leadership on teaching practice, and satisfaction with dual roles. Findings reveal that teacher leaders perform their leadership duties at a variety of times in an effort to protect their classroom teaching and seem to use the time they normally spend in planning and conferencing, as well as their own personal time. While findings reveal that most teachers enjoy the challenge of performing two roles they also indicated that they periodically become overwhelmed with the responsibilities of both roles. The study concludes that teacher leadership might adversely affect some teaching practices, as planning and preparation for instruction are affected, and teacher leaders' sudden shifts from leading to teaching affects their teaching focus. (Contains 41 references.) (JDD)