In The Best of All Possible Worlds, there are several closely related species of humanoids; the book opens as one of them, the Sadiri, who practice mental disciplines and have strong telepathic abilities, see their home planet destroyed -- only those who were off-planet at the time, very predominantly men, survive. They travel to Cygnus Beta, where many humanoid species co-exist, seeking to set up a new society and preserve their ways; they travel Cygnus Beta searching for taSadiri, whom they share ancestry with, in hopes of building their population. The novel follows a group of Terrans and Sadiri, ambassadors and scientists, travelling for this purpose -- the focus is the relationship between one Sadiri, Dllenahkh, and Grace Delarua, whose Sadiri language fluency and scientific background make her an ideal person to support the mission. The two definitely make for what feels like a play on Humans and Vulcans, but I do love Star Trek so that works for me.
I seldom give five star reviews but have for The Best of All Possible Worlds for a few reasons. "Very different alien societies/cultures meeting" is a genre I love and have read much of, but I feel like Lord has written a really interesting and unique book. The differentiation between the species is just significant enough to matter -- to pose issues of cross-cultural communication and some conflict, though much of this is actually between communities rather than species per se -- which makes for interesting plot points, and there is a good balance between personal relationships, broader socio-political issues, and philosophical and ethical questions. I cannot wait to read the next book.