The collapse of vapor bubbles in a subcooled liquid is studied under conditions that heat transfer is the controlling mechanism. Emphasis is placed on the effect of translatory motion and the presence of noncondensable gas on the collapse rate. The governing conservation equations are cast into appropriate dimensionless forms, and numerical solutions are presented for the bubble history with Jakob number, Pe´clet number, and dimensionless persistent bubble radius as parameters. The predicted collapse behavior agrees satisfactorily with experimental data which cover ranges of Jakob number from 7 to 45, Pe´clet number from 100 to 7700, and persistent bubble radius from 7.5 to 40 percent of the initial radius. The analysis also yields detailed information on the temperature field surrounding a collapsing bubble, with or without translatory motion. Results for the latter vindicated the anticipated inadequacy of the thin thermal boundary-layer assumption used in published analyses.