Hi,
Organization development is about increasing the organization's effectiveness through various interventions. Attrition is inevitable. No matter how good you are in the industry, people will leave eventually over a period of time. Before you could bring an external intervention, as an HR professional, one should identify the root causes of people leaving the organization. You could gather data from the exit interviews.
Examine the processes right from recruitment to performance appraisal to compensation. Try competency-based processes, whether for recruitment, appraisal, etc.
Interestingly, I just read in today's Economic Times or The Business Line about TCS's strategy in retaining talent. Despite being a massive recruiter, they have one of the lowest attrition rates at 10.3%. Why is this so?
They have used three strategies:
1) Employee engagement at all levels.
2) Finding the right fit employees through recruitment.
3) Giving employees opportunities to learn and grow through job rotation, exposure to the latest technology, etc.
So, it's up to the HR personnel to identify the right strategy for their respective organization based on the organization's mission and goals.
Most importantly, always get top management support for every event.
Good luck!