Yes, your wife can absolutely use your American Airlines AAdvantage miles, and there are two main ways to make it happen. The most common and cost-effective method is for you to book the flight for her directly from your account. When you search for an award flight on aa.com and select the flight, you simply enter her name and details as the passenger during the checkout process; the miles will be deducted from your balance, but the ticket will be in her name. The second method is to transfer the miles to her individual AAdvantage account. While this gives her control over the miles, it is not free; American Airlines charges a fee (currently around 0.5 cents per mile) to move miles between accounts. Unless she needs a small number of miles to "top off" her own balance for a specific flight, it is much more efficient for you to just book the ticket for her using your own account, as there are no "transfer" fees for booking a flight for someone else.