Cadmium is a well-known environmental pollutant. Rice is an important staple food for approximately half of the world’s populations and for people who depend on rice as a dietary staple, it has been shown to be potentially a major source of cadmium intake. In polished rice grains, a safe level threshold of 0.4 mg kg^-1 cadmium has been set by the Codex Alimentarius Commission of the FAO/WHO. Large genotypic variation in cadmium accumulation in the shoot and grain of rice cultivars have been reported. An understanding of the molecular and physiological mechanisms responsible for cultivar variations in cadmium tolerance and accumulation can help with the breeding of rice cultivars with high cadmium tolerance and low levels of cadmium accumulation in the grains. The aim of this study was to determine the relationship between cadmium tolerance and cadmium accumulation in rice and identify genetic loci for cadmium tolerance from a novel population. Initially a rapid screening system for cadmium tolerance was developed to determine the lowest concentration of cadmium which produce easily measurable differences in cadmium stress on the plants in a hydroponic system. Cadmium tolerance index for plant traits (root length, shoot length, root dry weight and shoot dry weight) were determined across the cadmium concentration used in a first experiment (0, 1, 5, 10, 20, 40, 70, 100 µM). The highest significant cultivar difference for the two rice varieties tested (cv. Italica Carolina and cv. Rata Boro) was obtained at 10 µM for root dry weight (P <0.001) and shoot height (P= 0.010). There were significant differences in total shoot cadmium and shoot cadmium concentrations between the two rice cultivars used in the first experiment. A significant cultivar by environment interaction for shoot cadmium concentration was also observed (p<0.05). There was a general trend of decreasing level of nutrient element content (manganese, copper and zinc) in the shoot with increasing levels of cadmium concentration. A second experiment was conducted using cadmium concentrations of 0, 10, and 40 µM with increased number of rice cultivars (four low and four high grain cadmium accumulating cultivar). Cadmium tolerance index was calculated and significant cultivar differences were observed at 10 uM for shoot height (<0.001) and root dry weight (P=0.005) only. In a third experiment a 10 µM cadmium concentration hydroponic solution was used to screen the Bengal and Assam Aus Panel population (203 rice cultivars) for the purpose of conducting genome wide association (GWA) mapping for cadmium tolerance. The most useful trait for tolerance to cadmium stress was found to be shoot length with significant cultivar by treatment interaction (p <0.001). Eighteen cultivars were found to be very tolerant to cadmium stress, one hundred and seventeen cultivars were moderately tolerant, while seventy cultivars were found to be sensitive. Using the GWAS, a number of potential genes directly related to cadmium tolerance were identified.