Jelinek was born in 1952 and grew up in the Los Angeles area.
Jelinek's dad helped build B-1 and B-70 bomber planes for a living. The CEO later told the Seattle Times that his father dissuaded him from going into the aircraft business.
The reason? Sales "always depended on the Democrats or the Republicans," and shifted with every new political regime change, Jelinek told the Seattle Times.
Jelinek went on to attend San Diego State University, which was also the alma mater of Costco co-founder Jim Sinegal.
next slide will load in 15 secondsSkip AdSkip AdIn 2010, Costco VP Richard Galanti said that Jelinek had been "around many of the people that started Costco since the very late sixties" during a conference call.
One such early Costco mover and shaker was Sinegal. Jelinek didn't just attend his alma mater — they also both worked at the retailer FedMart.
Mass Market Retailers reported that Jelinek took his first job at FedMart in 1969, and he worked there for 12 years.
Jelinek told the Seattle Times that while he was holding down a part-time job with FedMart, his dad said something that ended up encouraging him to stick with retail.
"He said, 'You know what? People will always have to eat,'" Jelinek said. "I never forgot that. You always know there's going to be work."
next slide will load in 15 secondsSkip AdSkip AdIn 1981, Jelinek left FedMart and worked at Lucky Stores for three years.
Finally, in 1984, Jelinek embarked on his long career at Costco.
Jelinek spent most of his time at Costco working in operations, according to Mass Market Retailers.
He received a major promotion in 2004, when he was named executive vice president of merchandising for the chain.
Jelinek ultimately succeeded Sinegal to take the top spot at Costco in 2012.
next slide will load in 15 secondsSkip AdSkip Ad"We are excited about Craig's elevation to his new role," Jelinek's predecessor said, according to Mass Market Retailers. "He is a highly seasoned retail executive, with over 25 years' experience at our company and over 35 years' experience in the industry."
For his part, Jelinek has touted Costco's ways of doing business, telling the Seattle Times: "We just stayed to our principles — it's what we do, take care of customers and employees and the people who are selling us merchandise."