Our Team Effectiveness Experts
Jennifer McCollum is CEO of Linkage, where she oversees the strategic direction and global operations of the Burlington, MA-based company. She has 20 years of experience building and leading businesses in the leadership space, with a focus on leadership development, assessment and analytics. Her area of expertise includes bringing analytic rigor to critical talent decisions by linking leadership behavior to corporate performance outcomes. The products she and her teams have built help global organizations across industries make the right bets on their current and future leaders at critical decision points: at time of hire, and when identifying high potentials, developing leaders and planning for succession.
Prior to Linkage, Ms. McCollum spent the last decade growing businesses within Corporate Executive Board (CEB), now Gartner. In her time there, she led product management within the leadership division, driving innovative solutions that helped organizations select, develop and place leaders at all levels. She also ran CEB’s Leadership Academies business, which developed more than 30,000 professionals in 2,100 companies and 50 countries and grew revenue at a 97 percent combined annual growth rate across five years.
Previously, Ms. McCollum served as CEO of IntraVision, a leadership consultancy she founded and successfully grew over the course of eight years while working across industries with public companies, start-ups, associations and non-profits. Her passion is creating vision, executing strategy and managing cohesive teams toward aspirational goals.
Ms. McCollum has a master’s degree in communications from the University of Stirling in Stirling, Scotland and an undergraduate degree from Wake Forest University in psychology and communications.
Senior Vice President of Research and Development
Mark Hannum is Senior Vice President of Research and Development at Linkage. He partners with clients to create better business results that incorporate both organizational justice and effectiveness. An organization development consultant by training, Mark’s focus has been on understanding and improving executive processes and decision making. Through his work with executive teams, leadership teams, and shared services organizations, his clients have credited him with helping them manage through difficult risks, improve business operations, lead and coach through acquisitions and integrations, and take advantage of growth opportunities.
Mark specializes in using the tools and methods of systems dynamics. He spent his early career working as a group problem-solving facilitator and systems-thinking trainer before moving on to leading organization change efforts and ultimately, acquisitions and integrations. He has been both an internal and external consultant, has held senior-level training positions, and has headed up a shared services human resources operation.
While at Hanover Insurance, Mark was engaged with the Center for Organizational Learning at MIT’s Sloan School of Management. He is currently ABD at Boston University in organization development and is writing a book with a colleague on the foundational processes of executive teams.
Mark earned a BA in Psychology and Philosophy from Bucknell University and an MA in Psychology from the University of Oklahoma before completing the doctoral program ABD.
Senior Vice President of Business Development
Maria Howard is Senior Vice President of Business Development at Linkage, where she oversees the global business development team. She brings more than 15 years of experience building and leading businesses in the professional services industry with a focus on leadership development, assessment and succession, and talent acquisition.
Maria's area of expertise include aligning business and talent strategies to drive measureable impact against organizational goals, and she has a passion for driving this growth through their most important asset–their people. She has brought to market innovative and integreated solutions, linking the talent lifecycle from hiring, retention, development and promotion resulting in differentiated leaders capable of growth in an ever-changing and disruptive marketplace.
Prior to joining Linkage, Maria spent the last decade growing commercial businesses within Korn Ferry. During her time there, she led several post-acquisition integrations, driving double-digit growth across solution areas. She started a new global function driving capaiblity to deliver the integration of KF Executive Search, Futurestep, and Advisory/Product businesses to the market. She has served as an executive sponsor on marquee accounts across life sciences, consumer, industrial and technology industries and has delivered global programs to clients and internal colleagues across NA, APAC, and EMEA.
Senior Vice President of Consulting
Jillian Ihsanullah, PhD, is Senior Vice President of Consulting at Linkage. She specializes in working with organizations to build values, people systems, and leadership experiences that accelerate the development and commitment of women, while enlarging talent pipelines.
Jillian has designed and facilitated a wide range of leadership development programs, including classroom experiences, action-learning teams, executive coaching, and executive retreats. Most recently, she integrated her passion for leadership with her expertise in measurement as the architect of Linkage’s Return on Leadership Development system, a unique offering designed to measure the bottom-line impact of leadership development efforts. Her clients include Aldo Shoes, American Airlines, GE Capital, General Motors, John Deere, Lockheed Martin, Mattel, McDonald’s Corporation, Morgan Stanley, Toyota, and The United Nations, to name a few.
Prior to joining Linkage, Jillian earned recognition for excellence in teaching undergraduate psychology courses at Purdue University. She previously worked at the Indianapolis think tank, Hudson Institute; cofounded Thought Labs, a social media consulting company; and ran Decisions That Matter, her own executive consulting and coaching business.
She holds a BA in psychology from Connecticut College and an MS and PhD in industrial/organizational psychology from Purdue University, where her research focused on measurement, decision making, and leadership styles.
Bernardus Holtrop is a Principal Consultant at Linkage. He is an expert group facilitator and executive coach who works with organizations both large and small, including many Fortune 100 companies. Bernardus designs and steers leadership development journeys that improve work relationships, cultivate organizational transformation, and deliver bottom-line results. Within his leadership work, he is passionate about two areas: emotional intelligence, working with leaders to deeply connect to themselves and others, and team effectiveness, fostering trust and (re)building relationships to create results. A global citizen with residences in the Netherlands and the United States, he translates leadership across cultures effortlessly.
Prior to joining Linkage, Bernardus was a strategy and organizational consultant and learning program manager at McKinsey & Company. He developed and ran a program that helped define ideal client service and teamwork, and then devised solutions that helped achieve goals in this focus area. He also managed and redesigned a program implemented to help senior partners become trusted counselors to their clients, as well as inspiring leaders to their teams. Bernardus was also the Chief Learning Officer at Mobius Executive Leadership, a US-based consultancy that is a spin-off of the Harvard Negotiation Project.
Bernardus earned an MS in electrical engineering from the University of Twente and an MBA in general management from the Rotterdam School of Management. He is also a certified transformational coach who helps individuals create breakthroughs in their professional and personal lives.
Dr. David Vaughn is a Principal Consultant at Linkage. His recent work has focused on helping clients navigate matrix management, deploy a coaching culture, build an internal consulting discipline, and develop senior leadership teams. David has in-depth experience facilitating these initiatives in the healthcare, insurance, financial services, consumer products, and light manufacturing sectors.
David uses his extensive coaching experience to help all of his clients, including C-level executives, bring out the best in themselves regardless of the context or business climate. He brings experience from prior general management positions and an acute organizational development mindset to his client engagements.
Prior to joining Linkage, David worked for Anheuser-Busch. As a Regional Director, he was responsible for the Wholesale Operations in seven Midwest and Southern markets. He was also a Director of Business Development and Division Vice President for the Anheuser-Busch subsidiary, Campbell Taggart. Both roles helped prepare him for his assignment to lead their internal consulting efforts, where he focused on business management consulting, operations analysis, sales service strategy development, route distribution planning, computer-based routing, information systems consulting, and hands-on leadership coaching at all levels of independent distributorships, from small to large.
David has also worked as an independent consultant on large-scale global organizational interventions in Asia, Africa, and South America. His work included developing and coaching the executive directors and their leadership teams and boards in how to effectively take on the identity of the organization and manage it as a single-minded group in the deployment of policy, strategy, and solutions to emerging opportunities.
David earned a BS in Industrial Engineering from Missouri University, an MA in Human Resource Management from Washington University in St. Louis, an MBA from McNeese State University, and a PhD in Public Policy and Administration from St. Louis University. He also received a Certificate in Theology from Concordia Seminary in St. Louis.