Our Values
The principles that guide everything we do
Excellence
We strive for 2.5% mastery in every vital sector of O2C operations.
Community
Building the world's largest, vendor-free network of O2C professionals.
Leadership
Everyone should think of themselves as a leader, regardless of role.
Purpose
Work should transcend routine - we share the magic that makes each day meaningful.
I've spent forty years in Credit and O2C, working across every operating model you can name. In that time, I've watched this profession evolve from back-office function to strategic capability. The teams that make that leap share three things: sound judgement, strong governance, and leaders who invest in their people.
Callisto exists to accelerate that journey. We bring together senior practitioners from leading organisations to share what actually works, prepare for what's coming, and raise the bar for the profession as a whole.
Whether you join us for a conference, a training programme, or ongoing membership, you'll find a community that values substance over theory and peer insight over vendor pitches.
I look forward to welcoming you.
Our Story
Mark Harrison begins his career as a Credit Controller
Decades of experience across Centralized, Decentralized and GBS environments
First Credit Matters conference
Launch of Callisto Academy
Callisto community expands to 50+ countries
Credit Matters XIV in Budapest
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