One of the questions designers face when putting together a proposal for a new client is addressing the obvious question: “How many designs do I get to see?”
There are differing philosophies on this point. Stefan Sagmeister notably shows clients only one design solution. Other designers show a veritable smorgasbord of designs, throwing as much as possible against the wall in hopes that something will stick (also known as the “shotgun approach”).
We are generally flexible in addressing client requests for a specific number of creative directions. Typically, however, we will present two distinctly different design directions. They vary in concept as well as execution (illustration vs. photography or typography driven). The exception is brand marks (aka logos), where we will show at least three design directions.
The thinking is that there are no soul mates in design (ie, “The One”) but you don't want to be too prolific in your design solutions, as this can muddy the waters. We find that clients value receiving a recommendation amongst the solutions shown. If you present too many solutions, you're likely not providing a focused approach to the client's problem.
Of course, once a client has reviewed the initial work, it evolves based on their inputs and we build in time for several rounds of design iterations. If you have really a great client (and we are fortunate to have more than a few) it's worth showing process sketches to give them a sense of how you arrived at the final design treatment. This allows them a window into your thinking and goes a long way toward having them buy off on the work.
Treat your clients as collaborators, not adversaries in the design process and you'll find that the work can benefit tremendously from their input.