IT Engineer here. Went from Help Desk (call center type work) to Desktop Support (face to face interactions) to now Systems Engineering where it's a mix of dealing with users, colleagues, and vendors. Every one of the jobs i have worked in list communication as the #1 most important ability. My achilles tendon is and i'm sure always will be introducing myself. "Hi, i'm E-ee-e-ethan" The biggest thing is being comfortable for me... If you know your stuff in meetings, presentations, conference calls, ETC i find I stutter much less.