Although there have been several calls for incorporating multiple levels of analysis in employee health and well-being research, studies examining the interplay between individual, workgroup, organizational and broader societal factors in relation to employee mental health outcomes remain an exception rather than the norm. At the same time, organizational intervention research and practice also tends to be limited by a single-level focus, omitting potentially important influences at multiple levels of analysis. The aims of this conceptual paper are to help progress our understanding of work-related determinants of employee mental health by the following: (1) providing a rationale for routine multilevel assessment of the psychosocial work environment; (2) discussing how a multilevel perspective can improve related organizational interventions; and (3) highlighting key theoretical and methodological considerations relevant to these aims. We present five recommendations for future research, relating to using appropriate multilevel research designs, justifying group-level constructs, developing group-level measures, expanding investigations to the organizational level and developing multilevel approaches to intervention design, implementation and evaluation. Copyright © 2014 John Wiley & Sons, Ltd.