An ultrasound catheter system can be configured to provide therapeutic ultrasound and imaging. An ultrasound catheter system can comprise a catheter having a distal portion. In several embodiments, a first ultrasonic element can be disposed in the distal portion of the catheter and can be configured to emit a first ultrasonic energy to enhance delivery of a therapeutic compound. In some embodiments, a second ultrasonic element can be disposed in the distal portion of the catheter and can be configured to convert a second ultrasonic energy that is reflected from an imaging site into an electrical signal.
