The standardized ileal digestibility (SID) of CP and AA was evaluated in soybean (Glycine max) meal, sunflower (Helianthus annuus) meal, rapeseed cake, and field pea (Pisum sativum) using 10 pigs and in lupine (Lupinus angustifolius) using 7 pigs. Pigs were fitted with either a T-cannula or a steered ileocecal valve-cannula. Diets contained 170 to 186 g CP/kg DM. Endogenous losses of CP and AA were estimated by feeding a N-free diet. The SID was calculated using the average of Cr(2)O(3) and TiO(2) as indigestible markers and corrected for type of cannula. The SID of CP was greater (P < 0.05) for soybean meal and pea compared to sunflower meal, rapeseed cake, and lupine. The SID of Lys and His were lowest (P < 0.05) in sunflower meal, and the SID of Met and Val were lowest (P < 0.05) in lupine. These results imply soybean meal and pea to be a high-digestible protein source relative to sunflower meal, rapeseed cake, and especially lupine, although all tested feedstuffs seem appropriate for inclusion in diets for organic pigs.