Through mapping the sociological origins of Palestinian doctors: their birthplace, class and family origin, early educational background, and university education, this chapter shows the social transformations of Palestinian communities during the late Ottoman and Mandate periods. It traces the development of the professional classes, from landed, mercantile, and religious notability, which converted, and sometimes supplemented, existing economic and cultural capital into professional education. It argues that throughout the Mandate period, the social origins of the professional community diversified to include families and individuals who gained mobility through sociocultural and economic capital. The chapter also looks at secondary and higher education as a meeting ground for the formation of lifelong professional and personal networks on a regional scale, as doctors were one of the only groups educated outside Palestine. The chapter builds on quantitative analysis of biographical data of about 400 doctors who worked in Palestine. Sources include biographical dictionaries, biographies and autobiographies, and various educational and employment lists.