This review investigates the effectiveness of ablative and nonablative fractional photothermolysis (FP) lasers for treating facial acne scars. Twenty-six studies (13 ablative FP, 13 nonablative FP) published between 2003 and January 2011 were reviewed. Quantitative and qualitative data from each article were examined and analysed. Four studies were split-face randomized controlled studies. While the data analysed were all clinically relevant and significant, there were some methodological differences between the studies. Outcomes included subjective and objective assessment of scar appearance, pre- and postoperative treatment, side-effects and pain scores. A small number of studies used three-dimensional optical imaging profiling and histology for objective assessment. Even allowing for methodological variability, ablative FP had an improvement range of 26–83% whereas nonablative FP had an improvement range of 26–50%. Patients who underwent treatment with an ablative FP laser experienced erythema for 3–14 days which resolved by 12 weeks, whereas patients who opted for the nonablative FP laser experienced erythema for between 1 and 3 days and this resolved within a week. A higher proportion of patients (up to 92·3%) who underwent ablative FP experienced postinflammatory hyperpigmentation (PIH) than those who had nonablative FP (up to 13%). The maximum duration of PIH in ablative FP was up to 6 months whereas in nonablative FP it lasted for up to 1 week. The procedure with ablative FP was relatively uncomfortable compared with nonablative FP. The pain score with ablative FP ranged from 5·90 to 8·10 (scale 1–10) and with nonablative FP from 3·90 to 5·66 (scale 1–10).