Method and apparatus are provided for use with systems applying laser energy to treat a selected dermatology problem. The method and apparatus protect skin not under treatment in skin regions affected by the laser by detecting, with a suitable sensor, at least a selected parameter in the skin region affected by the delivered laser energy and performing a control function to effect the desired protection by use of a feedback mechanism which is operative in response to an output from the sensor. For some embodiments, two laser pulses may be utilized, which pulses are spaced by a time which is preferably greater than the thermal relaxation time for affected regions not under treatment, for example an epidermis through which the energy is passed to an area under treatment, but is less than the thermal relaxation time of the area under treatment. The first of the pulses serves as a prediagnosis pulse which is clearly below the damage threshold for protected areas, with the sensor output for the first pulse being utilized to control at least one parameter of the second pulse.