It’s official: Matthew Charles Willsher is the chief executive officer of Nigeria’s number four mobile operator Etisalat.

Willsher became acting CEO for Etisalat after the company’s previous head, Stevan Evans, unexpectedly departed his post in August last year.

Willsher was Etisalat Nigeria’s former chief commercial officer as well.

And last week, Etisalat Nigeria officially announced its board’s permanent appointment of Willsher as its CEO.

“In under a year of his leadership Etisalat has recorded over 20% growth in its customer base, increase in spend per customer, significant strengthening of margins, and has maintained the No. 1 position on Customer Satisfaction,” Etisalat has said in a statement.

Willsher is a physics graduate from the University of Oxford. He also has a masters in management from McGill.

His experience has spanned executive roles for telecom operators in the United Arab Emirates, Malaysia, Hong Kong and Australia.

Meanwhile, Etisalat is Nigeria’s fourth largest mobile operator after MTN, Airtel and Glo Mobile.

According to the Nigerian Communications Commission’s operator data for March 2014, Etisalat had 18,722,613 subscribers, up from 15,759,810 subscribers in September 2013.

In comparison, the NCC says MTN Nigeria had 57,224,316 subscribers in March 2014, Airtel had 25,521,046, and Globacom (Glo Mobile) had 23,416,867 for the same period.