With the introduction of School Management Initiative (SMI) in Hong Kong schools in recent years, teachers' participation in decision making becomes one of the main themes in school management. By employing a model made of three dimensions, namely decision domain, decision level and decision involvement pattern, this study aims to investigate the patterns, processes and consequences of teachers' participation in decision making in SMI schools. The research adopted both quantitative and qualitative methods in studying two secondary SMI schools. A questionnaire was developed to survey teachers' involvement pattern of making decisions on the issues of technical and managerial domains at individual, group and school levels. 19 teachers from a SMI school participated in a pilot study to test the reliability and validity of the instrument. After a slight revision of the questionnaire as a result of the pilot study, teachers from the two subject schools participated in the questionnaire survey. A total of 105 copies of the questionnaire were distributed through a teacher at each of the two subject schools and there were 84 valid responses giving a return rate of 80 percent. Then the two principals and fourteen teachers from the two subject schools were interviewed to collect information for validating the results of involvement pattern obtained in the questionnaire survey and for studying the processes and consequences of participative decision making. The interviews were tape-recorded and transcribed into verbatim. Besides, documentary analysis on school profiles, plans, reports and magazines provided information supplementary to the interviews. Quantitative data were run with the statistical package of SPSS for Windows 6.1" while qualitative data were analyzed with the prepared theoretical framework. The results suggested the following points: 1. Teachers were more actively participated and more satisfied with the conditions for making decision after their schools