Since 1906, American Visiting Teachers have been providing services in schools for over 100 years. Social workers apply professional theories and skills in guidance services in school settings. In Taiwan, the Christian Children Foundation began to provide school social work programs in 1977. There are cities that conduct different practice patterns of experimental programs. Due to different development backgrounds of cities, there are three different practice patterns of school social work services. These patterns are called “On Campus,” “Out Reach,” and “Contract Out.” Until now, there were few evaluation studies available relevant to the strengths and weaknesses among these patterns in Taiwan. This study used literature analysis, in-depth interviews, and focus groups, sampling 12 school social works in Taipei City, Taipei County, and Hsin Chu City during 2005-2006. Based on these data, the study compared these three patterns and provided suggestions for future practice development and research.