In the present study, inverse methods are used to reconstruct trophic flows through the whole Newfoundland-Labrador Shelf ecosystem (NAFO 2J3KLNO) for the 1985-1987 period. This was a period of relatively constant biomass for the major species prior to the groundfish stock collapses. The whole-system model of the Newfoundland-Labrador Shelf is divided into 31 functional groups or compartments from phytoplankton and detritus to marine mammals and seabirds, including harvested species of pelagic, demersal, and benthic domains. The results are compared with a mass balance model using the Ecopath approach with the same data set. Successful development of the suite of ecosystem models proposed for the Comparative Dynamics of Exploited Ecosystems in the Northwest Atlantic (CDEENA) program wil provide powerful new tools to evaluate the impact of human and environmental factors in a variety of Atlantic shelf ecosystems.