Schlumberger developed the first telephone chip cards for France Telecom and the Swedish telecommunications operator Telia in the early 1980s. The company developed ties with telecommunications operators in several countries, and played a role in industry-wide efforts to develop new digital mobile communication standards, particularly the GSM transmission standard (Global System for Mobile Communication). Schlumberger designed its first SIM card in the early 1990s for the launch of GSM in Europe, and this led to the use of microprocessor card technology as an access and security solution for mobile telephony worldwide, in 3 billion handsets today.