This study identified 67 professional competencies needed by teachers/advisors to carry out the 4-S program. All competencies were considered to be of moderate to very high importance.;The target population for this study consisted of vocational agriculture teachers, home economics teachers, principals, and national advisors who had participated in the 4-S program. The whole population was selected for the study. The primary instrument for data collection was a questionnaire used with teachers and principals. The secondary instrument was an open-ended interview conducted among national advisors. Descriptive statistics were used to analyze data obtained from the questionnaires. Multiple regression was used to predict how variables participate and influence observations; t-tests and analyses of variance were used to test differences in respondents' perceptions of the professional competencies when demographic data were considered. The alpha level was set a priori in all cases at the.10 level of significance. Content analysis was used to analyze data from the interviews.;Findings indicate that there were significant differences in perceptions of the respondents when considering teaching methodologies, oral communication, written communication, program evaluation, and technical knowledge. No significant differences were found when considering competencies in understanding human behavior and program execution. There were no significant differences in the perceptions of teachers and principals regarding the importance of the competencies when age, years of experience as a 4-S teacher/advisor and educational level were considered. Significant effects were obtained for training received, previous experience, gender, position, and region. Through the multiple regression procedure, positive correlations were found between training received with teaching methodologies competencies; long-term courses with oral communication competencies; training means and position with understanding human behavior competencies; and age with technical knowledge competencies.