Solidarity corresponds to virtuous social behavior, including personal freedom and responsibility, civic friendship, benevolence, reciprocity, and cooperation. These attributes are fundamentally good for individual persons and communities of work. Solidarity is therefore vitally important to the practice of humanistic management. This paper aims to provide management insights into the cultivation of solidarity. The paper begins by developing a theoretical framework to understand solidarity in business context, with attention to philosophical and theological connotations. An empirical research model is presented in the form of a survey instrument to test for indications of solidarity in the workplace, and this measure is used to test several hypotheses regarding the positive associations of solidarity with validated measures of workplace engagement. Research results show that it is possible to identify and analyze workplace behaviors associated with solidarity. Data analysis confirms the validity of the model and demonstrates the positive associations of the hypotheses, based on empirical study of 40 workplaces and 399 employees. Moreover, the condition of whether the workplace was a public or private organization was found to affect the main relationship between solidarity and workplace engagement. The paper concludes with suggestions for practicable, tangible workplace behaviors based on the model, offering guidance in the pursuit of humanistic management.