Technical Abstract: Available water and nitrogen (N) are typically the biggest constraints to dryland spring durum (Triticum turgidum L. var. durum) production in the northern Great Plains (NGP). A common rotation for spring durum is with summer fallow, which is used to accrue additional soil moisture and N for the subsequent crop. Annual spring-seeded forage crops, well adapted in the NGP, utilize less water than cereal grains, including durum, and may be suitable to replace summer fallow. We conducted an experiment from 2002 through 2006 comparing yield, quality, and water and nitrogen use of durum and three annual forages, barley (Hordeum vulgare L.), barley interseeded with pea (Pisum sativum L. ssp. arvense (L.) Poir.), and foxtail millet (Setaria italica (L.) Beauv.) in two-year rotations. Perennial forage alfalfa (Medicago sativa L.) and durum in rotation with summer fallow also were included. Averaged over five years, alfalfa had higher forage yield, water use, nitrogen accumulation, and forage quality compared to annual forages. The annual forages had similar preplant and postharvest soil water contents, but barley and barley-pea had higher yields and water use compared to millet. The barley-pea intercrop had superior forage crude protein (CP), neutral detergent fiber (NDF) and N accumulation compared to barley and millet, but acid detergent fiber (ADF) and nitrogen recovery index (NRI) were similar among annual forages. Averaged over four years, preplant soil water and residual N content were greater for durum following fallow than for durum following annual forages, resulting in reduced fertilizer N requirement and greater yield, water use, grain N accumulation and NRI. Years differed for forage and durum productivity, primarily due to precipitation amount and timing. Replacing summer fallow with annual forages reduced durum grain yield by 727 kg ha-1 but increased forage yield by 4.9 Mg ha-1. Although replacing summer fallow by forages reduced durum yield, their inclusion in rotation with durum is warranted if forage or biomass production is a goal.