The deal comes two months after Salesforce announced its biggest deal ever, buying data visualization software company Tableau for more than $15 billion.
Salesforce already offers tools for dealing with field service, which involves keeping track of employees heading out to perform maintenance for customers.
"Salesforce Field Service Lightning, built on Service Cloud, harnesses the latest in dispatching, mobile workforce empowerment and IoT technologies to empower companies to connect their entire service workforce on a single, centralized platform. With the combined capabilities of Field Service Lightning and ClickSoftware, Salesforce will be positioned to lead the way to the future of field service," Salesforce said in a statement.
ClickSoftware was founded in 1997 and has 829 employees listed on LinkedIn. The company's customers include Bosch and Vodafone.