New excimer-pumped laser dyes based on p-quaterphenyl are described and the associated performance parameters are presented. A discussion of the variations in the performance parameters found is made in terms of dye chemical structures. Most of the dyes studied are significantly better than the chosen reference dye BBQ. The best dye in the series (dye 3) is stabilized both by ring-alkylation and by ringbridging. The net effect is the production of a new dye with a lifetime ten times greater than that of the reference dye BBQ.