Dear Joe,
Our work together on St. Tropez has ended but I'm hopeful that I will soon have the pleasure of working with you again.
Looking back on the trajectory of this project I am motivated to write you to first and foremost thank you for having the confidence in our firm to engage us to provide the structural design of St. Tropez. I take pride in every project I do, but this project has brought me particular satisfaction. As you know, I have worked with a very wide range of developers here in the U.S. and overseas. Rarely have I seen a corporate culture that encourages excellence, efficiency and productive results. Your pragmatic approach made our job so much more gratifying.
I must tell you that I am not accustomed to writing this type of letter, however, my admiration for the way you directed the job inspired me to do so and to enthusiastically look forward to working with you on future projects. Please feel free to call upon us for upcoming proposals. I will certainly do my very best to provide you with fees that reflect our positive experience with your firm.
Sincerely,

Ysael A. Seinuk