17 Longest Running TV Shows of All Time, From "Grey's Anatomy" to "SVU"

• Seasons: 19
• Episodes: 591

For a good portion of the late 20th century, Lassie was America's Dog. The lovable series recounts the everyday adventures of Lassie (a collie) and boys Jeff and Timmy Martin. Even if you've never seen "Lassie," you most likely know of the show's influence through pop culture references or the famous quote, "Lassie, come home!"