As part of the NHL's Hockey Is For Everyone initiative, Klingberg was selected as the club's ambassador due to his engagement off the ice in humanitarian work which positively impacts a diverse, marginalized or underserved population.
On the ice, the native of Gothenburg, Sweden has skated in two games in the 2019 Stanley Cup Playoffs and has logged one assist (0-1=1). During the 2018-19 regular season, he registered 45 points (10-35=45) in 64 regular-season games with Dallas. Klingberg ranked 11th in the NHL with 24:32 time on ice per game, establishing a new career high, while he also shared second amongst League blueliners and third among all Dallas skaters with a career-high five game-winning goals. Amongst NHL defensemen, he was tied for sixth in power play goals (5) and tied for 10th in power play points (5-15=20), and ranked fourth among all Stars skaters with a career-best five power play goals. The blueliner finished third on the Stars with 35 assists and fourth with 45 points, leading team defensemen in both categories and reaching the 30-point mark for the fifth consecutive season, becoming the first defenseman in franchise history (since 1967-68) to record at least 30 points in each of his first five NHL seasons.