The main objective of this study was to propose a program for developing fundamental (essential) competencies for headmasters and headmistresses of basic education schools in the Sultanate of Oman. The professional competencies were investigated based on the professional needs of the headmasters and headmistresses. From the objectives of the study, the following research questions were investigated: 1. What are the fundamental competencies of headmasters and headmistresses in the light of their professional needs in the basic education schools? 2. Are there statistical significant differences (a =0.05) among the headmasters and headmistresses in their professional needs based on gender, years of experiences and academic qualifications? 3. What is the suggested program for developing fundamental competencies in the light of professional needs of headmasters and headmistresses in basic education schools in the Sultanate of Oman? The population of this study were all 625 headmasters and headmistresses of basic educational schools in Oman in the year of the study 2008/2009. Using a random sampling method, a sample of 325 headmasters and headmistresses were chosen. For achieving the objectives of the study, a questionnaire with 54 items was developed. The questionnaire consisted of six main dimensions: organization, planning, leadership and guidance, decision making, communication and evaluation. Furthermore, the questionnaire was tested for its validity and reliability. The main results of the study were. 1. The headmasters and headmistresses are in a great need of developing their fundamental competencies in the areas of organization, planning, leadership and guidance, decision making, communication and evaluation. 2. There are no statistical significant differences (a =0.05) among headmasters and headmistresses in their needs of developing fundamental competencies based on gender, years of experiences, and academic qualifications. Based on the findings, the study recommended the followings: adopting the fundamental competencies that were found in this study as essential competencies that need developed for headmasters and headmistresses in the basic education schools in the Sultanate of Oman. It also recommended using the proposed program in this study in designing training programs for developing performance of headmasters and headmistresses. In addition, this study recommended conducting furthermore studies, in developing other programs, which were not covered in this research, for headmasters and headmistresses.