A particle sizing technique that operates in conjunction with laser velocimetry is proposed. The technique uses a non-intrusive single particle counter based on a pulse height analyzer. It is expected that a size range of 0.1 um to 10 um will be attainable. Lower size limits would require ensemble measurements which cannot be readily used with laser velocimetry, since the size of each particle is necessary. The technique has been successfully used to measure spray droplets between 5 and 300 um. It is expected that with proper development the dynamic size range will be extended to 0.1 um, including irregularly shaped particles as found in laser velocimetry.