Invertebrate secondary production, or the formation of invertebrate biomass through time, has been estimated in many freshwater benthic habitats It has been a major research theme for the North American Benthological Society (NABS), and many of its members have made significant contributions to the subject, both before and during the existence of J-NABS. Although sonic benthic production work Occurred before 1960, the major methods were developed primarily during the 1960s and 1970s Most of these methods also were applied in terrestrial and marine environments The main focus of our paper is how secondary production has been used as an essential variable in facilitating answers to a wide variety of ecological questions Benthic freshwater production studies before the inception of J-NABS were primarily related to life history, interpopulation comparisons, niche overlap/competition, predator-prey relationships, differences in production/biomass (P/B), energy flow, the trophic basis of production, habitat-specific microdistributions, effects of pollution and clams, and quantification of aquatic-terrestrial linkages Since that time, new applications have been related to habitat-specific macrodistributions, quantitative food webs, experimental and tracer-based studies of trophic resources, chemical flows/stoichiometric relationships, diversity/function relationships, influence of nonnative species and landuse changes, implications of metabolic theory, and the importance of meiofauna vs macrofauna J-NABS has been a major Outlet for many of these applications, has probably included a higher fraction of papers incorporating secondary production analysis than any other journal, and probably will continue to be a leader in this area