In 1983, Children's Hospital became a charter member of the Children's Miracle Network, joining 21 other hospitals participating in the first Children's Miracle Network Telethon. That year, the local telethon raised $95,487, all of which remained at Children's Hospital for the direct benefit of its patients.

Each year, funds raised through the telethon are used to purchase new and replacement medical equipment to help Children's Hospital remain on the cutting edge of pediatric health care. Some years, the goal is to purchase a wide variety of equipment for departments throughout the hospital. In other years, the telethon proceeds may be earmarked for one or two exceptionally costly items, such as the hospital’s first Lifeline neonatal transport van in 1984 or the hospital’s first MRI scanner in 2000.

In addition to funding equipment purchases, a portion of donations to each year’s telethon is also targeted to support the hospital’s Open Door Policy. Since treating its first patient in 1937, Children's Hospital has maintained an Open Door Policy. It ensures no child will ever be denied care at the hospital due to race, religion, national origin, gender or their parents' ability to pay their medical bill.

Throughout the years and due to the tremendous generosity of the people of East Tennessee, the event has grown at a spectacular rate. In June 1994, the 12th annual Children’s Miracle Network telethon broke the $1 million mark for the first time, raising more than $1,015,000 to purchase a variety of medical equipment.

Just eight years later, in June 2002, the 20th annual Children’s Miracle Network telethon reached an even more significant and exciting milestone, topping the $2 million mark for the first time. The 2002 telethon’s total of more than $2.2 million was a testimony of the progress Children's Hospital has made over the years – it was the largest telethon of any kind ever conducted in East Tennessee. That year the telethon funded the purchase of a new automated chemistry analyzer for the hospital’s Laboratory and new infant ventilators for Respiratory Care.

In 2006, for the first time in its history, the telethon date was changed and the event's length was shortened for the local broadcast. Traditionally scheduled on Saturday evening and all day Sunday on the weekend after Memorial Day, the 2006 local telethon was moved to a single day, Sunday, March 12. In 2007, the event ramained on a single day, but was moved to January 28.

The national CMN Telethon continues to be broadcast each year the weekend after Memorial Day. It airs locally on 10News2, the sister station of WBIR-TV.

Throughout the history of the event, the CMN telethon for Children's Hospital has been broadcast by WBIR-TV 10; it has grown and succeeded in large measure because of the dedication, expertise and talent of each camera person, on-air personality, producer and behind-the-scenes employee. WBIR-TV has been dedicated to Children's Hospital by providing live television coverage every year to the national and local segments of the CMN broadcast.