Efforts are underway to recover and maintain the native biotic assemblages of Lake Tahoe.  Both state and federal agencies continue to develop strategies to restore the lake’s only native trout, the Lahontan cutthroat trout (Oncorhynchus clarki henshawi) within the basin, and prevent the further decline of native forage fishes within Lake Tahoe.  In the last 125 years, numerous nonnative species have been introduced into the lake.  Here we discuss the invasion history of Lake Tahoe.  We then focus on the effect of five nonnative species (lake trout- Salvelinus namaycush, mysid shrimp- Mysis relicta, largemouth bass- Micropterus salmoides, crayfish- Pacifastacus leniusculus, water milfoil- Myriophyllum spicatum) on food web interactions, species assemblages, and nutrient processes.  Special emphasis is placed on how these species may inhibit the recovery of cutthroat trout native forage species.