The clinical diagnosis of many dermatological conditions suffers from inadequacies and a histopathological analysis of skin biopsies remains the standard for confirmation of a diagnosis. We suggest that near-infrared (IR) spectroscopy may be a suitable non-invasive, objective tool for characterizing skin conditions. This paper will highlight our in vivo near-IR spectroscopic characterization of skin tumors presented for differential diagnosis of skin cancer. In vivo visible and near-IR spectra (400–2500 nm) were collected from actinic keratoses, basal cell carcinomata, benign nevi, dysplastic nevi, actinic lentigines and seborrheic keratoses by placing a fiber optic probe on the skin. Linear discriminant analysis (LDA) was used to determine whether spectra could be classified according to lesion type and resulted in accuracies of 70–98% in differentiating benign from pre-malignant or malignant lesions. Near-IR spectroscopy is a promising non-invasive technique for the screening of skin lesions. [Copyright &y& Elsevier]