top of page

About EmploymentSource 

Our History 

25+ years of shaping careers and lives

Established in 1996, Employment Source is an independently owned Human Resource Consulting firm in Billings, MT that operates nationwide. Our experience as Hiring Experts and Human Resource Professionals has given us a solid professional background to provide you with the very best talent at the highest level of service across market sectors, specialties, and industries.

Our Experience

It's The Way We Do Business, With Our Candidates and Our Clients

  • High quality project management, execution, reliable service, and integrity are the cornerstones of our company.

  • We are proud that our professionals help create an atmosphere of open communication and trust.

  • Let us be your first SOURCE for success. At Employment Source, compromise on quality customer services is not an option.

  • With our experienced, dedicated recruiters asking the right questions and listening for the right answers, we qualify more candidates and create superior matches.


Happier Employees

Faster, Efficient, Successful Staffing

Fewer Headaches

Less Turnover




Terry Mammenga Co-Owner

Terry’s career has spanned from accounting and payroll to Human Resource to corporate management. He has a bachelor’s degree in business and holds the certification of Senior Professional in Human Resources (SPHR), as well as being OSHA Safety certified. Terry continues to use his expertise in accounting, payroll, Human Resources, and management. 


Sandie Mammenga Co-Owner

Sandie holds Bachelor’s and Master’s degrees in Montana Universities. Sandie’s career has covered education, administration, management, staff development, and employee training. Sandie manages all our marketing and digital presence. 


Julie Dunn Office Manager / Payroll Specialist

Julie has been with Employment Source since 2003.  She holds a degree in Marketing and Management from MSUB. Julie manages the daily operations and provides administrative training and support. She processes and administers weekly, bi-weekly, semi-monthly, and monthly payrolls for all our clients. Julie also maintains the books, prepares standard and special reports as needed as well as processing all state and federal payroll taxes assuring their correct and timely filing.  


Kari Shelton Recruiting Specialist

Kari worked as the marketing and sales supervisor and corporate sales trainer, while also holding a position in customer service for a travel agency for 12 years prior to joining our team in 2017. Kari is a dedicated recruiter who is passionate about people and finding the perfect fit for both the customer and candidate. Kari is friendly and outgoing and always ready to help applicants find the right position to match their skills. Come in and see Kari for the professional help you need. 


Pamela Hampton Administrative Assistant 

Pamela started working as our Administrative Assistant in July 2021 bringing with her 15 years of customer service and administration experience. She was the PTA leader at a local elementary school for seven years. When not working, Pam enjoys spoiling her family and four-legged grandchildren. Pam’s friendly face will probably be the first one you see when you come to Employment Source and her customer service and clerical skills will help make your job search an enjoyable experience. 

bottom of page