AbstractThis study aims to investigate teacher OCB (Organizational Citizenship Behaviors) dimensions, aspects, and indicators that serve as the basis for developing an instrument to measure teacher OCB. With the Indonesian context, this study is based on a qualitative study conducted by Shaheen et al. The instrument developed in this study uses a summated rating scale model based on self-reports. This study with Design and Development (D&D) research design went through some stages, namely 1) analyzing instrument item by focusing on content, construction, and language; 2) consulting to psychometric and language experts to obtain expert judgment; 3) validating the content through FGD with teachers and principals and trying out the instrument to the teachers individually to see its readability; 4) revising the instrument based on the first trial; 5) testing the instrument to the teacher group; 6) quantitatively analyzing the feasibility of the instrument using statistical methods; and 7) submitti.....