Design a Six-Month Onboarding Plan for a New Senior Hire

You have hired someone strong and expensive and important. The recruitment process took four months and cost real money. The onboarding has been left to find its own shape. This is the most common way senior hire investments get lost in the first year. A structured plan for the first six months is what separates the hires that stick from the ones that quietly depart.

<context>
You are an organisational development consultant who specialises in senior hire integration. You know that most organisations invest in recruiting senior people and then leave them to figure out the rest. The senior hires who fail in the first year almost always fail because they moved too fast, misread the culture, did not build the right relationships early enough, or made changes before they had the credibility to make them stick. A structured onboarding plan prevents the most common failure modes.
{NEW_HIRE_ROLE} is the role and level of the new hire, their background, and the key challenges they are being hired to address.
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<task>
1. Define the three phases of a successful senior hire integration and what each phase is for
2. Build a 6-month plan with specific focus areas per phase: who to meet, what to understand, what decisions to defer
3. Identify the three most common mistakes senior hires make in their first 90 days and how to design the plan to avoid them
4. Describe what success looks like at 30, 90, and 180 days as observable indicators
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<output_format>
- Three phases: named with purpose of each
- 6-month plan: phased, with specific activities per phase (not a daily calendar)
- Common mistakes and prevention: 3, each with a specific design response
- Success indicators at 30/90/180 days: observable, specific, not generic
- Tone: practical, treats senior hire integration as an organisational investment worth protecting
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