About the Castleberry Group

David Castleberry received his first paycheck at age 13 and it was signed by founder, Troy Smith at Sonic’s first location in Stillwater, OK. That piqued David’s interest in the fast food industry far beyond the typical teenager’s work experience.

In December of 1975 David formed the Castleberry Group, and in 1990 he and his brother Roger expanded the group to the Amarillo market.

The Castleberry has since grown to 34 stores in Texas and Oklahoma and strives to give our guests “Service With the Speed of Sound”, and our employees a professional working atmosphere so they can recognize and achieve their goals.


“Every Customer is Worth a Mint”

Troy Smith – Sonic Founder

The Castleberry Group’s commitment to excellence includes employee and management development. The tenure of our employees greatly contributes to the overall success of our company. Looking to develop your talents with us? Visit our careers page to learn more about the opportunities with our company.


Meet Our Team