This study aims to evaluate the extent of School Learning Action Cell (SLAC) Session Implementation and Teachers Competencies in Cluster 4 of Calamba, Division of Calamba City. Specifically, it sought to answer the following questions: 1.           What is the extent of the School Learning Action Cell (SLAC) Session Implementation in the Cluster 4 of the Division of Calamba 2. What is the level of Teachers Competency 3. Does the School Learning Action Cell(SLAC) Session Implementation have significant relationship to the Professional Development of Teachers in terms of Functional Competencies in the Cluster 4 of Calamba, Division of Calamba City? 4. Does the School Learning Action Cell(SLAC) Session Implementation have significant relationship to the Professional Development of Teachers in terms of Behavioral Competencies in the Cluster 4 of Calamba, Division of Calamba City? In conducting this study, a descriptive study method was used to collect the data and information needed to test the hypothesis and to answer questions concerning the extent of the school learning action cell (SLAC) session implementation in the cluster 4 of the division of Calamba. The instrument used was questionnaire in the form of checklist and Five-Likert scale to gather information headed in the accomplishment of the study. The respondents of the study is composed of one hundred eight (108) teachers from Cluster 4 of the Division of Calamba, Calamba City. The statistical treatment used in this study included frequency counts, equivalent percentages, mean average, and standard deviation. The two way ANOVA was used to determine the whether there is a significant relationship between the extent of school learning action cell (SLAC) to the level of professional development of the teachers. Based on the prior findings of the study, the researcher found out that the extent of the extent school learning action cell (SLAC) session implementation and the professional development of teachers in terms of functional competencies and behavioral competencies are all very high. This means that teachers professional development is significantly related by the extent of the SLAC sessions.