A growing body of research indicates that teachers have different job skills, knowledge, behavior, attitudes, and concerns at different points in their careers. Many of these changes seem to follow a regular developmental pattern from which three stages can be discerned. Stage I is the survival stage, during which beginning teachers are concerned about their skill in maintaining classroom control, teaching content areas, and in continuing to develop their teaching abilities. Teachers at Stage II, during the second, third, and fourth years of teaching experience, adjust to the teaching situation and gain confidence in handling most classroom situations. These teachers are more likely to be able to assess their own needs and seek assistance. In the third stage, after five years of teaching experience, teachers reach a professional maturity and are skilled in a variety of techniques. They are more committed to their careers at this stage. Studies have shown that: (1) The first four years of teaching is the primary time of job skills acquisition; (2) By the third stage, most teachers change their techniques rather than their philosophy of teaching; and (3) Stages of professional development have a significant effect on personal development. Appended is a table showing a matrix of the three stages and the changes in professional characteristics experienced at each stage. (FG)