Alphanumeric speech recognition is one of the more challenging problems we face: There are many possible ways to implement it. When recognition goes well, callers are more satisfied; when recognition is not good, callers can get frustrated. This session covers how to design for improved alphanumeric recognition. It also includes various tips and tricks—constraining grammars versus using an n-best list, using web services to validate input, leveraging prefiller to improve initial phoneme recognition, and how to compare recognition methods.