Williamsport High School's postsecondary program, founded during World War I, evolved significantly during the World War II era.

Eleven days after the Nazis invaded Holland and Belgium, the school established an Emergency Training Commission to adapt its vocational program to meet defense training needs by developing highly skilled metal workers. Williamsport was one of the nation's first training programs adapted to meet war preparation needs.

More than 5,000 students were enrolled in classes that were in session 24 hours a day to meet the training needs of local companies involved in manufacturing for the defense industry during World War II.

Williamsport Technical Institute was formally established on the foundation of tremendous growth the program achieved during WWII. In addition to defense industry training, the program again retrained returning veterans – many of whom were disabled – for new positions in business and industry.

Even before the passage of the "G.I. Bill," WTI gained a reputation for excellence among veterans and others. It became one of the nation's most prominent providers of training for individuals with physical disabilities.

In 1951, WTI began a Vocational Diagnostic Program that was the first in the nation to combine a job-trial method of exploring career options in its extensive instructional shops with occupational counseling and guidance for disabled individuals. The National Rehabilitation Association cited the groundbreaking efforts as "an inspiration to rehabilitation workers everywhere."

WTI was officially approved for training foreign students in 1953. Williamsport Schools Through the Years, a document chronicling activities, reported, "The fame of the Williamsport Technical Institute as an outstanding vocational center has spread beyond the borders of the United States….Educators from many foreign countries have enrolled at WTI to study our methods of vocational education in an effort to set up similar centers in their own countries."

The institute's leaders were among the first Pennsylvanians calling for the establishment of a statewide community college system in the 1950s and 60s. They developed a "strong neighborhood concept" – inviting students from school districts surrounding Williamsport to attend WTI on tuition basis. They later encouraged those districts to serve as local sponsors of a community college built on the foundation of the technical institute.