The article presents the results of a comparative study of human resource development (HRD) in two groups of knowledge-intensive firms: those working in the information technology (IT) field and in advertising/public relations (PR) field. One hundred Russian medium-sized enterprises participated in the study. The questionnaire was developed on the basis of the European quality standard ‘Investors in People’. The study findings suggested that the differences in HR practices aimed at personnel development between two groups of companies were statistically significant. Thus, in the advertising/PR companies, HRD practices were used more actively and effectively, with particular emphasis on providing timely feedback and involving employees in the decision-making process. In IT companies, formal assessment tools were used more often, while in advertising/PR companies, more informal and individualized approaches were more prevalent.