Executive Team

David Grace


David Grace is an accomplished travel industry veteran with more than two decades of experience leading strategic and management teams for Enterprise Holdings and National Car Rental, and most recently, Deem, Inc. Having been an integral part of the 2019 acquisition of Deem by Enterprise Holdings and then signing on as Deem’s Chief Revenue Officer (CRO), Grace was named President at Deem in November 2020.

Grace began his career at National Car Rental and quickly moved into leadership roles, including Vice President of Sales and Vice President of Strategic Accounts, where he led nationwide sales. He later transitioned into executive roles at Enterprise Holdings and, currently, at Deem.

Grace is a global travel and mobility thought leader, and a well-known industry speaker. He frequently presents at live and virtual events around the world for industry organizations including Business Travel News and GBTA, and is quoted regularly in trade publications.

Christina Woronchak


Christina is passionate about global travel. She has traveled the world and has devoted her career to the business travel industry, leading sales and client management teams for leading global, hospitality and travel management companies.  As Deem’s Chief Revenue Officer, Christina leads the sales and customer experience teams. In that capacity, she is responsible for accelerating the company’s global growth through new customer acquisition, strategic partnerships and customer retention and expansion. Christina began her career in Montreal in the hospitality industry. She then transitioned to business travel management, and after a 17+ year career with American Express Global Business Travel, she joined Deem in December of 2019. She believes the rapid evolution to a digital first economy should extend to business travel and that Deem is best positioned to deliver a modern platform and the best possible traveler experience.

Neil Markey


Neil has more than 20 years experience in fast paced, high growth software, e-commerce, direct sales, mobile, and gaming companies. He is a seasoned technology executive with strong product and business acumen. Neil has a strong technical background and has successfully implemented PCI compliance for several companies. He has transformed growing organizations and developed cultures where technology professionals thrive. Prior to Deem, Neil reshaped the way that companies use technology at CafePress, PlayFirst, Kazaana and Stella & Dot. He graduated from Staffordshire University with a 1stclass honors degree in computer science. At Deem, Neil will be implementing next generation technologies in order to advance the business travel market.

Dave Shiba


Dave is a senior software finance and operations executive with a demonstrated ability to execute against a focused strategy and transform organizations into industry leaders. He has a unique background spanning venture-backed private companies, large public companies and a multi-national accounting and consulting firm. He has deep hands-on experience with SaaS B2B and online B2C e-commerce business models. Prior to Deem, Dave was the Chief Operating Officer and Chief Financial Officer at VerticalResponse (a Deluxe Company) and a General Manager at Deluxe after VerticalResponse’s acquisition by Deluxe. Dave was also CFO at Informative, Inc. and Corporate Controller at Travelocity. He has also held financial management positions at SGI and Arthur Andersen.

Todd Kaiser


Todd is an e-commerce veteran and entrepreneur who has served as a product management, marketing and technology leader to many premier global consumer brands. He has successfully delivered highly scalable and innovative products across the consumer, SMB and Enterprise market segments. Todd joined Deem from ONEtechnology, a firm that has created a platform for developing progressive web applications without writing code. His previous travel industry experience includes GetThere, Orbitz, TRX/Concur and LesConcierges.

Todd Kaiser


As Vice President of Human Resources, Michelle is responsible for developing Deem’s global HR strategy and leading all areas of HR including talent acquisition, talent development, total rewards, and HR operations. She has a passion for building and sustaining a culture of engagement and belonging for all employees, and for bringing global teams together to solve tough problems in innovative ways.

Michelle is a change and transformational HR leader with 25+ years of global experience focused on integrating the people strategy with the business strategy to drive performance and growth and to promote organizational health. Her success comes from her proven ability to build high-performing, goal-exceeding teams and develop progressive, business-aligned HR strategies and initiatives typically in a context of rapid growth and change.Prior to joining the Deem Team Michelle has held executive roles at a variety of technology and consulting companies including Mixpanel, AppSense, Trend Micro, and PricewaterhouseCoopers.

Paul Houle


Paul has had over 20 years of professional business experience and success, leading strategic change, sales, solution consulting, professional services, and support and training. Prior to joining Deem, Paul founded, led and managed an award-winning 1st-of-its-kind best practice delivery model for the spend management SaaS industry at Procuri and Ariba, Inc. Now, Paul works as the Vice President of Customer Experience at Deem, Inc. Paul holds a Bachelor of Science degree in Business Administration from the University of New Hampshire. He enjoys coaching his son’s baseball teams, playing sports, being outside and staying active.

Tahnee Perry


Tahnee Perry is a marketing executive with 15+ years of travel industry experience. She fosters a passion for excellence in execution and builds high-performance teams. She currently leads the brand, marketing and demand generation efforts for Deem. In the past, she drove creative and marketing strategy for B2B information solutions company, Northstar Travel Group, and for travel research authority, Phocuswright. Prior to Phocuswright, Tahnee held various sales and marketing roles for Aspen/Snowmass ski resort and ran a communications team for services organization, Totalcare. She's a frequent industry speaker and guest lecturer at Stanford University.

John F. Rizzo


John has more than 35 years of experience helping guide some of the world’s most successful technology companies through start-up phases, major product launches, branding and marketing campaigns, rapid growth, acquisitions and IPOs.   He has raised well over $200M in venture capital financing and was a key early-stage contributor to companies that are today delivering well over $325B in combined sales with combined market capitalizations well in excess of $2T.   He has two IPO's and six exits under his belt, most recently when Deem was acquired by Enterprise Holdings ($22B in revenue in FY20.)

Before joining Deem, he was Chief Marketing Officer, Chief Customer Officer, and General Manager with an IT software company that grew from $325M to $505M in sales during his two-year tenure. The company was taken private in a $4.5 billion transaction – over a 75% premium from the time he joined the company. Prior to this John was Chief Marketing Officer in a cloud software provider, where he helped grow the business from $75 million to $150 million in revenues in 24 months and completed a successful $1.75 billion IPO. John has served as CEO at several early-stage startups with successful exits and early in his career held senior leadership roles at Apple (1st Macintosh team), Intel (FLASH memory), and Oracle (Network computing.)  He also is a board member of Untangle (security software), X2AI (AI-based mental health care), Circa.co (virtual events marketing platform), Filld (mobile fueling), and the Santa Fe Opera.  

John currently resides in Santa Fe, New Mexico, where he's involved in a range of community and innovation initiatives, one of which, the New Mexico Innovation Triangle (NMIT), aims to create 25,000 incremental innovation and tech jobs in the state.  He makes frequent trips to the Silicon Valley as he consults for Deem's President, David Grace.