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Introduction and aim: Pain due to a light moving mechanical stimulus, dynamic mechanical allodynia, is a protruding symptom/sign in subgroups of patients with peripheral neuropathic pain and frequently as troublesome as spontaneous ongoing pain. The objective of this thesis was to survey psychophysical details of dynamic mechanical allodynia using a novel semi-quantitative method. In addition, the psychophysical characteristics of dynamic mechanical allodynia in the secondary hyperalgesic zone after an intradermal injection of capsaicin were probed with regard to similarities and differences of that phenomenon compared to such allodynia in peripheral neuropathic pain. Methods: Using a semi-quantitative method brush-evoked allodynia was induced in the innervation territory of the lesioned nervous structure in patients by lightly stroking different distances of the skin 2 or 4 times with brushes of different widths or while varying stroking velocity or brushing force. In study III the patients were also examined in the area outside the flare after an intradermal capsaicin injection in the corresponding contralateral site to the area of painful neuropathy, i.e., in the secondary hyperalgesic area. Age- and sex-matched controls injected with identical amounts of capsaicin were examined in a corresponding area. In all studies the intensity and duration of brush-evoked allodynia was recorded using a computerized visual analogue scale. The total brush-evoked pain intensity, including painful aftersensation was calculated as the area under the curve. Following each stimulus, the subjects selected pain descriptors from a validated instrument. In study II the repeatability of brushevoked allodynia was examined within and between days in patients with peripheral neuropathic pain. Results: Significantly increased total brush-evoked pain intensity was demonstrated with increased brushing length and number of strokes, higher brushing force and lower stroking velocity but not whil