This is a balloon catheter having at least two lumens. One of the lumens is a large working lumen. The balloon catheter is especially useful as a guide catheter or micro catheter and may be used in a variety of therapeutic and diagnostic procedures. In particular, it has value in treating neurovascular embolic strokes in combination with other devices which are delivered to the stroke site through that working lumen. The remainder of the lumens typically are used to inflate and to deflate the balloon.