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Visible reflectance spectroscopy (VRS) has been used to reconstruct lake sediment chlorophyll a concentrations. Despite good concordance between inferred and measured chlorophyll a values, questions remain as to whether this spectral technique is tracking past changes in aquatic primary production, or simply recording a diagenetic signal. In this study, we critically evaluate how well VRS chlorophyll a determinations track past trends in aquatic primary production using sediment cores from several lake systems with well-known trophic histories. Our study sites include Arctic, boreal and prairie lakes that encompass a gradient of trophic states. In general, our spectrally inferred chlorophyll a values tracked past trends in lake trophic status consistent with historical measurements of production, or as inferred by independent proxies of primary production. We conclude that VRS chlorophyll a inferences …