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Agile is a framework for a way of working in which: 

• experts are empowered, to take ownership and create high-quality solutions,
• the gap between IT and Business is bridged, through input and validation by a business-representing Product Owner,
• transparency, alignment and early escalation (asking for help) are key,
• short cycles lead to adapting and improving plans,
• and we experiment with process improvements to gain efficiency.

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For this reason work with large estimates is broken down into smaller, workable pieces (that we can still test to validate a piece), and re-estimated.

A recommended tool/game for estimating together with a group is: https://planningpokeronline.com/

Sprinting or Continuous Flow

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• Agile Manifesto (free, self-paced 1 page)
• Scrum Guide (free, self-paced,  pdf 14 pages)
• Jira beginner's guide to Agile (free, self-paced, 90 minutes, certification option)
• Scrum Competencies on Scrum.org (free, self-paced, 30 minutes including sub-pages)
• Scrum Master Learning Path on Path on Scrum.org (free, self-paced, 8 hours, certification can be bought)
• Scrum Master Practice Assessment on Scrum.org (free, 30 questions, 30 minutes, 85% pass rate)
• Product Owner Learning Path on Scrum.org (free, self-paced, 8 hours, certification can be bought)
• Product Owner Practice Assessment on Scrum.org (free, 30 questions, 30 minutes, 85% pass rate)

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