Two new C-level appointments at GMS

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GMS

Global Message Services (GMS) is pleased to announce two new C-level appointments that will further strengthen our leadership team. 

Strategic Account Director Sarah Keller has been promoted to Chief Global Enterprise Officer. Former Vice President for Asia, Middle East and Africa, Amer Siraj, is now Chief Commercial Officer. 

Sarah is a telco expert with over 25 years of experience under her belt.  She joined GMS in 2015 and swiftly rose through the ranks to become its International Business Development Director in 2018. She later took on the position of Strategic Account Director, giving a powerful boost to our global expansion. 

In 2020, Sarah was recognised among the top 100 most influential people in the telecom industry by ROCCO Research.  

In her new role, Sarah will continue curating growth opportunities for GMS together with her Global Enterprise and International Hubs divisions, expanding GMS’ global footprint.  

sara keller gms
Sarah Keller
Chief Global Enterprise Officer



GMS’s role to “bridge the gap” between Enterprise and MNO will be firmly cemented with the new focus to connect the top 100 Global Enterprises. I am very excited to take on this new challenge.



Amer is a seasoned professional with over 20 years of experience in telecom operations and go-to-market consulting with global impact. He joined GMS in 2017 and has been instrumental in establishing global outreach, particularly with several operators in the Middle East and Africa region, large telco groups and enterprises. Under his regional leadership, GMS has built innovative and impactful propositions and entered several unique strategic partnerships. 

Besides his go-to-market positions, Amer has acted as advisor with start-ups and GSMA. His projects have been widely recognised at global forums.  

In his new role, Amer will be responsible for creating new sales opportunities for international messaging. He will also manage the day-to-day sales operations at GMS.  

amer siraj gms
Amer Siraj
Chief Commercial Officer

I am delighted to lead the commercial team. Our company is at the forefront of innovation in the industry and a leader in several ways. We are in a unique position to address our customers’ communication needs, be it for mobile operators or enterprises of any scale. We will continue to strive for the best, always challenge the status quo and stay hungry forever.



GMS Chief Executive Officer Charles Upchurch said: 

“With their extensive experience in business development and client management, Sarah and Amer will offer us valuable on-the-ground perspectives on how to drive business growth. They will be instrumental in helping us achieve new strategic partnerships and alliances, expanding our international sales presence.”



About Global Message Services (GMS)  

GMS is an international messaging service provider for mobile operators and enterprises worldwide. GMS is the messaging hub for A2P, P2P, P2A and RCS traffic exchange and a trusted messaging protection partner. We provide mobile operators with full network control to ensure secure message delivery. The GMS CPaaS solution enables enterprises from all over the world to engage their customers with tailored and interactive content delivered via a host of channels including SMS, Push, Viber, WhatsApp and RCS.  

Our goal is to help our partners and clients grow. We provide expert knowledge of local and international markets, and create high-quality, turnkey solutions, tailoring them to fit the needs of each client. Headquartered in Baar, Switzerland, GMS also maintains 5 regional offices worldwide. 

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