Hi,
Technically that looks correct and Request.QueryString should in theory url decode that as You & I
But sometimes there are differences between theory and practice. What I would try is change the way you are rendering the link like this and see if that works
<a href='mypage.aspx?item=You+%26+I'>link text</a>
spaces can be encoded as + instead of %20
also make sure you use quotes around the href.
Hope that helps,
Joe