Joe Popevis

Joe Popevis

Nelnet Diversified Services President

Joe Popevis has served as the president of Nelnet Diversified Services since 2013. He provides strategic direction and senior leadership for the operations and technology that support all of our business lines. Joe also develops leaders, teams, and training programs for thousands of associates, and lends valuable expertise in organizational process improvement and operational efficiency. Joe’s dual passions for developing people and serving partners and customers led to the creation of strategies that make Nelnet a premier employer with exciting growth opportunities.

Christy Phillips

Christy Phillips

Consumer Services and Client Support

Christy Phillips is an accomplished leader with over 21 years of experience in the student loan industry. She currently leads all aspects of operational management for consumer loans, including client support, loan application processing, contact center support, account maintenance, and due diligence. With a background in operations, systems, marketing, and customer care management, Christy is relentless in her pursuit of customer-focused ideals and experiences.

Brent Fausett

K. Brent Fausett

Consumer Services Technology Delivery

Brent Fausett’s focus is building a diversified consumer loan strategy to capitalize on new industry and asset class opportunities. He is responsible for delivering modern software platforms to support the present and future needs of Nelnet and our clients. Brent’s over 24 years of technology and finance industry experience includes building new, modern, cloud-based loan systems for third-party originators and servicers of consumer and business loan assets.

John Turner

John Turner

Information Technology Delivery

John Turner brings over 15 years of senior leadership experience in student loan servicing. He leads IT Delivery, providing direction for daily business functions and organizational success. John is responsible for the technical implementation of Nelnet Loan Servicing’s Direct Loan contract. He oversees system strategies, capacity planning, and enhancements delivery, while ensuring prioritized projects are delivered as expected to support the business needs of the organization and our clients. He oversaw the migration of not-for-profit servicing solutions to Nelnet’s technology platform, and also ensured the successful transition of more than 25.6 million federal loan customers to Nelnet’s servicing technology between 2009 and 2019. 

Jen Burkey

Federal Services Operations and Business Process Outsourcing

Jen Burkey has nearly two decades of experience in the student loan servicing industry, including managing servicing operations, contact center, and back-office processing. She directs customer experience and communication strategies, while overseeing Nelnet’s commercial business process outsourcing operations for clients in a range of industries. Jen’s extensive background has enabled her to drive customer experience improvements for our clients. Jen and her teams leverage our strong data analytics capabilities to make strategic decisions and suggestions, helping our clients increase their revenue and achieve success.

Jill Leitl

Federal Services Operations

Jill Leitl brings over 32 years of experience in the student loan industry, including a detailed technical understanding of loan management and strong partnerships within government services. She managed both development and infrastructure teams before moving into business operations, giving her a unique perspective into the organization. Responsible for hundreds of associates, she values all the ideas they bring to the table. In collaboration with other leaders, Jill works to set up associates for success and make Nelnet a great place to work.

Jeff Riekenberg

Jeff Riekenberg

Compliance, Training, and Document Services

Jeff Riekenberg’s nearly 30 years of experience in the student loan industry includes leadership over most aspects of loan servicing to improve customer and processing experiences. Currently he supports all incoming document, imaging, and mail for Nelnet Diversified Services, as well as leading the first line of defense for our compliance and risk team, including direct oversight of training and quality. Jeff’s leadership was key in improving efficiency and mitigating risk during the process of scanning and imaging over 132 million documents in our repository.

Melissa Marks

Melissa Marks

Renewable Energy

Melissa Marks brings over 23 years of experience with Nelnet, including client support services, product development, mergers and acquisitions, innovation, and business development. She currently leads our renewable energy services, providing subscriber acquisition and support solutions for community solar developers. Melissa is focused on helping clients achieve their growth goals, while tailoring solutions to meet their unique business needs. She is a natural collaborator focused on business-to-business services and solutions development.

Mark Heiser

Mark Heiser

Business Development

Mark Heiser’s extensive background in finance and capital markets provides him with a unique perspective in developing strategic partnerships with clients. Areas of focus to best serve their portfolio and customer needs include full-service outsourcing, backup servicing, and technology solutions. Mark has led many of Nelnet’s initiatives into asset class diversification and investment into new technologies to serve an emerging fintech landscape. He has worked with top lending companies to form partnerships that leverage Nelnet’s experience and offerings in the fintech industry.

Peter Sanderson


Peter Sanderson has 28 years of experience building companies, business sectors, and strategic partnerships across technology, finance, and education markets. In his 18 years with Nelnet, he’s led teams through critical growth initiatives, organizational optimization, acquisitions, and complex institutional and systems deals. Peter is an innovative and passionate strategist who leans on his extensive background to cultivate new markets and competitive opportunities. He is focused on evaluating and expanding all business growth initiatives while leveraging Nelnet’s multi-functional teams and diverse, customer-centric solutions.

Lisa (Dixon) Lien

Financial Management and Oversight

Lisa (Dixon) Lien brings over 22 years of finance and accounting experience to Nelnet, with 19 years specifically in the student loan industry. She uses her expertise to perform a wide range of activities to provide financial management and oversight to Nelnet Diversified Services. She also provides oversight of cash management and reconciliation activities for commercial and consumer loan programs. Lisa’s passion in leveraging the power of data in critical decisions and long-term strategies helps Nelnet deliver premier professional services, as well as the most valuable insights to customers.