Immediately after graduating from MIT, Shockley joined Bell Telephone Laboratories in New Jersey. He initially worked on radar research related to World War II.

During the war, Shockley contributed to military research focused on improving radar systems. His work during this time expanded his knowledge of electronics and materials science.

After the war, Shockley shifted his focus to solid-state physics and the potential of semiconductors. He led a team to develop a solid-state amplifier to replace vacuum tubes.

Although Shockley's theoretical ideas were crucial, the first working transistor (the point-contact transistor) was physically constructed by John Bardeen and Walter Brattain in December 1947. While Shockley wasn't directly involved in that experiment, his leadership and theoretical framework were essential. This invention revolutionized electronics.

Dissatisfied with the point-contact transistor, Shockley dedicated himself to creating a more robust and practical transistor. In 1951, he developed the bipolar junction transistor, a device that became the foundation of modern electronics.

Shockley continued his research at Bell Labs, publishing extensively on transistor technology and solid-state physics. He became a prominent figure in the scientific community.

Shockley, along with John Bardeen and Walter Brattain, was awarded the Nobel Prize in Physics for the invention of the transistor. This recognition solidified his place as one of the most important scientists of the 20th century.