The top 27 software companies serving the public relations industry

• Private equity firms have invested in the public relations software industry in recent years, giving rise to a $4.5 billion industry.
• Business Insider identified the top 27 PR software companies that use technology to help clients monitor media coverage and manage crises.

Communications chiefs and public relations agencies are scrambling for technology solutions to gain an edge over their competitors.

That's given rise to a $4.5 billion industry of firms providing services from social media analysis to press release distribution to crisis detection.

Business Insider identified the top 27 PR software companies. They include new players like measurement platform Memo that have signed on clients like Google and Walmart by offering exclusive publisher data; established PR firms; and legacy players like Cision, which is trying to be a one-stop shop for PR pros' needs.

Subscribe to read the full list: 27 software firms that companies like Amazon and Unilever use to supercharge their public relations efforts