Sheila: Every state requires registered architects to hold a license. Check with your state (usually under Sec of States office) to see if the individual is a registered architect. Some states but not all require firms to also register and hold licenses to practise architecture in their particular state. If the person is not registered be careful because depending on the size of your project your building inspector may not accept the plans for permit without a "stamped" set of drawings. Check with your building inspector he may have knowledge of the individual or firm you are looking at.
Dick