A standardized Canadian Agricultural Nitrogen Budget (CANB v2.0) model was developed to calculate the agro-environmental indicators Residual Soil Nitrogen (RSN) and Indicator of Risk of Water Contamination by Nitrogen (IROWC-N). This paper describes how the two indicators were simulated at the Soil Landscape of Canada (SLC) polygon scale (1:1 million). The CANB v2.0 model, which contains three main modules, was developed using Digital Visual Fortran. The RSN module calculates Residual Soil Nitrogen for the census years 1981, 1986, 1991, 1996 and 2001. The main improvement over a previous version is the harmonization of the methods used to handle RSN in Eastern and Western Canada. RSN is calculated as the difference between all N inputs (fertilizer, manure, biological fixation, and atmospheric deposition) and all N outputs (N removed during the crop's harvest and N lost from ammonia volatilization and from denitrification, but assuming no N leaching during the growing season). The IROWC-N module takes the calculated RSN output and calculates the amount and concentration of N lost from the soil. This module uses a semi-dynamic water balance with daily weather data to calculate accumulated daily precipitation minus potential evaporation (P-PE) during the non-growing season (Sept 1 - March 31) for each year from 1979 to 2003. These over-winter (P - PE) values are then used to calculate the concentration and amount of N lost for 4 years centered around each census year. The scaling module aggregates and classifies the results from the SLC level up to regional, provincial and national scales. Statistics Canada, through it's Census of Agriculture, provides the main data inputs: the acreages for all the major agricultural crops and their associated yield, as well as the type and number of livestock. Various coefficients and assumptions, based on experimental values and expert opinion, are incorporated in the calculations. Validation of the model's output was carried out using independent data from nitrogen industry sales. There was good agreement between the calculated fertilizer N application rate from the CANB model and the fertilizer N sold in each province, especially in 1996 and 2001. The model was also used to test various agricultural policy scenarios and to evaluate the sensitivity of RSN to the N2O:N2 ratio resulting from denitrification. Keywords: landscape nitrogen model, Agri-Environmental Indicator, Soil Landscapes of Canada, Census of Agriculture