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Green Cabbage certification classes
Become a Certified Deal Negotiator
Counter supplier strategies, sharpen deal messaging, and run complex deals with control. Earn your certificate and 8 hours of continuing education credit that can be applied toward certifications such as CPSM, ISM, and other procurement credentials. 
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Choose your class

Quarterly schedules are listed on each card below.

Class 1
Negotiation Master Class 1
Implementing the Deal Leverage Management Process

Build a repeatable leverage model and information strategy before renewal discussions begin.

Class 1 Details

Quarterly schedule

 Monday - Friday, 12:30pm to 2:00pm ET  

Jul
Week of Jul 13 - 17, 2026
Oct
Week of Oct 12 - 16, 2026
Class 2
Negotiation Master Class 2
Countering Supplier Sales Strategies and Effective Deal Messaging

Neutralize supplier narratives and align stakeholders with messaging that holds under pressure.

Class 2 Details

Quarterly schedule

 Monday - Friday, 12:30pm to 2:00pm ET 

Aug
Week of Aug 17 - 21, 2026
Nov
Week of Nov 9 - 13, 2026
Class 3
Negotiation Master Class 3
Leading Complex Deal Negotiations

Run complex deals with cadence, decision control, and clean accountability across teams.

Class 3 Details

Quarterly schedule

Monday - Friday, 12:30pm to 2:00pm ET

Sep
Week of Sep 14 - 18, 2026
Dec
Week of Dec 7 - 11, 2026
Request a 30-minute live preview

 Join our monthly Class Preview at No-Cost, a live session led by a subject matter expert designed to give you a clear snapshot of our certification class approach and value.

What you get

Live preview, sample materials, and recommended attendee roles based on your deal profile.

Learn from an expert practitioner

Practical instruction, built from real supplier and buyer-side negotiation experience.

Andrew Ozlowski
Andrew Ozlowski
CSO, Green Cabbage Inc.
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✓20+ years in procurement and negotiations
✓Led enterprise supplier negotiations and risk reviews
✓Supplier-side industry practitioner
Andrew graduated from With 20-year career in complex information technology solution sales and consulting with companies including SAP, Computer Associates, Kronos, and Accenture. Andrew combines supplier-side and buyer-side experience to teach teams how to control the negotiation process and drive better outcomes.
"The goal is to communicate leverage clearly enough that the supplier changes their behavior."