This paper addresses the depth distributions of implanted hydrogen (1H) in n-type GaAs and the asso-ciated damage in the crystalline material. Secondary ion mass spectrometry measurements are used to demonstrate the presence of hydrogen atoms in the implanted material and to obtain the range profiles of these atoms for fluences of 5E14 and 5E15 cm-2. The nature and the distribution of the resulting lattice damage are studied using transmission electron microscopy. Elevated temperature implants are shown to alter the range profiles and to increase the TEM-visible damage.