Sorghum grown in semi-arid regions is often exposed to drought and/or high temperature stress during reproductive development. The impact of short episodes of drought or high temperature stress and relative sensitivity of different stages of reproductive development to these stresses is not well understood. The objectives of this research were (a) to quantify the impact of short episodes of drought or high temperature stress; and (b) to identify most sensitive stage (s) to drought and/or high temperature stress during the reproductive development. Two experiments were conducted to understand the responses of sorghum to drought or high temperature stress. In the first experiment, plants were exposed to four water treatments (fully irrigated control; drought stress from boot leaf emergence to flowering; drought stress from flowering to seed-set; and drought stress from seed-set to mid seed fill). Drought stress at flowering resulted the lowest seed-set and seed yields., when compared to stress at other developmental stages. Drought caused significant changes in resource allocation depending upon timing of stress and sink strength; smaller sink-size (seed-set) increased allocation to vegetative parts, while larger sink size decreased allocation to vegetative parts and/or mobilized resources from vegetative to reproductive parts. In the second experiment plants were grown at daytime maximum/nighttime minimum temperature of 32/22ºC until 30 days after sowing (DAS) under fully irrigated conditions. Thereafter, plants were exposed to 40/30ºC (high temperature, HT) for 10 d at different stages (10 d prior to flowering, at flowering, 10, 20 and 30 d after flowering). High temperature stress delayed and/or inhibited panicle emergence. Periods of flowering and 10 d prior to flowering were most sensitive to HT stress causing maximum reduction in seed-set (seed-numbers) and seed yield. Seed yield losses during post flowering stages at HT were mainly due to decreased seed-size.