This is a two center, open label, ascending dose study. Subjects with at least two measurable melanoma lesions will receive a single intralesional injection of 10% PV-10 solution into each of one to twenty (20) target lesions. Additionally, one to three measurable untreated non-target lesions will be followed for assessment of bystander response. Systemic and locoregional adverse events will be monitored over the study interval. Dose escalation will be made only if no subjects at the first dose level have a Grade 3 non-hematological or Grade 4 hematological toxicity over a period of two weeks after PV-10 administration. Subject accrual and PV-10 administration at the second dose level will be stopped if more than 1 subject has a treatment related Grade 3 non-hematological or Grade 4 hematological toxicity within a period of two weeks after PV-10 administration.