The Aerospace & Defense (A & D) industries maintain a high level of interest in the expansive amount of work performed in developing and qualifying Pb-free solder alloys. The three main areas of interest continue to be thermal cycle, mechanical shock, and vibration. The past twenty years have seen an unprecedented increase in alloy development such that the concepts of “generations of solders and “families of solders” have been coined to help manage the numerous individual alloys on the market today. This paper will discuss work done with Pb-free solder alloys, many with the addition of constituents focusing on varying property enhancements. The purpose is to provide a “snap shot” summary of progress to date and relate perspectives both as advantages and concerns solely in a constructive manner to aid researchers in planning their next steps in development and qualification of these alloys.