 <p>You should use percent encoding to escape characters in your query string, see <a href="http://tools.ietf.org/html/rfc3986" rel="nofollow">RFC 3986</a>. This <a href="http://stackoverflow.com/questions/5366007/why-does-the-encodings-of-a-url-and-the-query-string-part-differ">previous StackOverflow post</a> contains some useful background information about URI encoding.</p> <blockquote> <p>Initially my main concern was fields that contained parentheses. I will be converting this query into a SQL server query and I need a way to ensure that I do not confuse a parentheses in a field value with one that is intended for grouping</p> </blockquote> <p>If this might be a problem then it sounds like your application will be susceptible to SQL injection. You should be escaping any external data before constructing an SQL query.</p> <blockquote> <p>/api/companies?q=(CompanyName eq Microsoft Or CompanyName eq Apple) And State eq California</p> </blockquote> <p>Based on this example you could take advantage of the URI query string to better represent your query:</p> <pre><code>/api/companies?CompanyName=Microsoft%20OR%20Apple&amp;State=California </code></pre>