The number of persons sentenced to prison for drug crimes increased by 95.5 percent between 1988 and 1990 but declined by nearly 10.2 percent in 1991. States reporting the largest declines were Kansas, Oklahoma, Florida, and Oregon. The only State reporting a significant increase was Illinois. The decline in drug arrests is related to the fiscal crisis of State and local governments, drug asset and seizure laws, and lower drug use. The NCCD projects that prison populations will continue to grow despite reductions in admissions due to the passage of mandatory minimum sentencing statutes and lengthier prison terms for certain crimes. Although national estimates of jail populations are not available, the NCCD expects jail populations to grow less than prison populations. Parole populations will grow at a rate similar to prison populations but, in some States, parole populations will increase rapidly due to early release mechanisms. The NCCD predicts the Federal and State inmate population in the United States will reach 1 million by the end of 1994. 5 tables and 3 figures