With its high spatial resolution and excellent detection capability, high-frequency ultrasound is a valuable tool in clinical studies, biomedical research, and nondestructive testing (NDT) of high value manufacturing (HVM). However, a major bottleneck in further progress is the development of ultrasonic transducers for high-frequency applications. In the paper, we introduce basic principles of ultrasonic transducers and briefly review existing ultrasonic transducer techniques. Following this, we address current technical challenges of high-frequency ultrasonic transducer techniques and provide practical solutions, illustrating our recent efforts to develop state-of-the-art high-freq uency ultrasonic transducer arrays. Finally, we discuss the future prospects of high-frequency ultrasonic transducer techniques.