Although professionalism remains important to the study and practice of public administration, its features have remained unclear. Whether public managers share a professional identity has yet to be empirically tested. In this article, we test a model of professional identity among public managers, using a national sample of city managers, the first profession in public administration. Both public administration in general and city management in particular lack institutional characteristics—such as mandatory programs of specialized training or a monopoly over entry into the field—that mark traditional professions such as medicine or law. Using five commonly found professional identification attributes, we test a structural equation model of professional beliefs among city managers with data from a national survey. We find evidence of city managers’ professional identity across four attributes: belief in professional associations, belief in public service, belief in self-regulation, and sense of calling. City managers’ beliefs about autonomy, however, were unrelated to other aspects of their professionalism.