"Tutorials in Introductory Physics" is based on extensive teaching experience and more than twenty years of research in which the Physics Education Group has sought to identify and address common difficulties that students encounter in studying physics. Development of the tutorials was motivated by the conviction that in order to develop a functional understanding of the material students need more assistance than they can obtain through listening to lectures, reading the textbook, and solving standard quantitative problems. "Tutorials in Introductory Physics" is intended to supplement these traditional forms of instruction by providing a structure that promotes the active mental engagement of students in the process of learning physics. The materials are equally appropriate for algebra-based and calculus-based courses. Working together in small collaborative groups, students help one another go through the steps in reasoning necessary for the construction and application of important concepts and principles. The tutorials have been rigorously class-tested at the University of Washington, at other research universities, and at two-year and four-year colleges. This First Edition of "Tutorials in Introductory Physics" builds upon the Preliminary Edition. In addition to new and revised tutorials on mechanics, electricity and magnetism, and waves and optics, the First Edition also includes tutorials on selected topics from hydrostatics, thermodynamics, and modern physics. In all cases, , a complete tutorial sequence consists of a pretest, worksheet, homework assignment, and examination questions that serve as cost-tests. The student texts consist of the tutorial worksheets andhomework assignments. Pretests are included in the Instructors Guides: For these instructional materials to be most effective, it is important that course examinations include qualitative questions that emphasize the concepts and re