Members include communications and digital service providers, telephone companies, cable operators, network operators, cloud providers, digital infrastructure providers, software suppliers, equipment suppliers, systems integrators, and management consultancies.

The Forum has 800+ member[1] companies (including the world's 10 largest telecommunications service providers[2][3]) that collectively generate US$ 2 trillion in revenue and serve 5 billion customers across 111 countries.

[4] TM Forum was founded as the OSI/Network Management Forum in 1988 by eight companies to collaboratively solve systems and operational management issues with the OSI protocols.

TM Forum hosts a variety of digital and in-person events year-round.

In September 2022, TM Forum held its first in-person event post Covid-19 pandemic when Digital Transformation World (DTW) 2022 opened doors at the Bella Center, Copenhagen.