Laboratory Corporation of America and Walgreens announced an expansion of their year-old collaboration by planning to put at least 600 testing centers in stores around the country.

“This reflects our commitment to transform our stores into neighborhood health destinations,” Stefano Pessina, executive vice chairman and CEO of Walgreens Boots Alliance Inc., said in a joint news release.

The companies announced they would begin offering specimen-collecting services in seven Walgreens stores in June 2017, the closest being in Morrisville, as a “proof of concept.” Apparently that’s panned out as the partnership is expanding to 16 stores in Florida, Colorado and Deerfield, Ill.

Expansion to 600 stores could take about four years. LabCorp has about 2,000 patient-service centers around the country already.

Appointments for LabCorp at Walgreens locations can be made at LabCorp.com/Walgreens, and LabCorp has an online patient portal and smartphone app. Information about LabCorp at Walgreens, including locations, is available at www.walgreens.com/findcarenow.

LabCorp is one of the country’s leading medical-testing companies with $10 billion in reported net revenues in 2017. Based in Burlington, it is Alamance County’s second-largest employer with 3,000 local employees, according to the Alamance Chamber.

Walgreens operates about 9,800 drugstores across the country, about 400 of which have healthcare clinics or other provider retail clinic service.