Stock assessments of commercially important fishes are conducted knowing that environmentally-driven va ability can be incorporated into assessments are controversial and there are few assessments that explicitly incorporate environmental factors in any way. Long-term databases have been increasingly mined in the last 20 years to develop indices or indicators that summarize environmental variability. Even when environmental time series are not used, the fishery-independent time series from ichthyoplankton surveys have proven invaluable to estimate spawning stock biomass trends for stock assessments. Univariate or multivariate indices are used in management frameworks either to assess performance of a fishery or to provide thresholds for management action. The Pacific sardine is one of the few assessments with an environmental control rule to provide a threshold for management action. I discuss the development of this indicator and its use in management. I use the sardine example to highlight some problems that can arise when environmental indices are reassessed. I also discuss the development of new and potentially more robust indicators.