Why this book? This seminal question can be addressed by two intertwined answers. First is the generic one related to the need for a book in this genre, and the second is specific to the untold story of the jati of Kayasthas in the encyclopedic form we have attempted here. Issues of identity and heritage in particular are broached while addressing the first part of the question. The second is then to address what, in general, does the book bring to its readers. The last but not least segment offers a personal account of the impressionistic motivations of the authors, which also includes the choice of methodology.