"To lead the sector" means to be at the forefront or in a dominant position within a specific industry or field. It signifies being the top or most influential company or organization in that particular sector. Full definition
The tech industry continues to fuel leasing activity, leading all sectors for the third consecutive year. (us.jll.com)
They're also more likely to emerge from a down market by leading their sector in gains. (tsinetwork.ca)
Our market - leading sector specific careers guides are the most influential and successful publications available to students today. (targetjobs.co.uk)