This article discusses demand and unmet need for family planning (FP) in Nepal. In developing countries, unmet need for contraception is an estimated 1 in 5 married women of reproductive age. If needs were met, fertility would decline by an average of 18%. FP is needed by all men and women of reproductive ages who desire a stop to, or a spacing of, childbearing. FP programs usually focus only on married couples. Unmet need refers to the difference between an expressed fertility preference and actual lack of contraceptive use. The current unmet need for FP in Nepal, among currently married women aged 15-49 years, was 27.7% in 1991, and 31.4% in 1996. 22.7% in 1991, and 28.5% in 1996, had met the need for FP for spacing or limiting purposes. 21.5% in 1991, and 25.9% in 1996, had met the need for limiting childbearing. The total demand for spacing or limiting was estimated at 50.5% in 1991, and 59.9% in 1996. Unmet need during 1991-96 increased by 0.74%. Met need during 1991-96 increased by 1.16%. The total demand for FP increased by over 9 percentage points. Unmet need for limiting increases linearly with parity and increases in a U-shaped pattern with age. Unmet need varies inversely with education. Unmet need is attributed to weakly held fertility preferences, perception of low risk of conception, lack of contraceptive information, unacceptability of contraception, opposition from husband to contraceptive use or perceived costs, fear of side effects, and inadequate FP services. The importance of these factors may vary between settings.