The term 'Baby Boomer' was originally coined to capture the generation of people born around the time of the end of the second world war up until the early 1960's. Plentiful in number, the baby boomers have been the backbone of the UK economy in recent decades and generally employers have had it good in terms of the number of available candidates to fill vacancies.

However, for the old baby boomers, retirement is on the horizon and this poses a complex two-tier problem for employers.

Tier 1: the brain drain phenomenon. A mass exodus of employees take decades of experience, knowledge, and invaluable know-how that cannot simply be taught on induction to new recruits or picked up by way of short term handover by the remaining workforce.

Are employers concerned about the loss of this invaluable reserve? Yes, according to recent new research by Robert Half. The research reveals that 74% of finance directors in the UK are concerned that the loss of their experienced workers will have a negative impact on business in the next two years. Furthermore, the anxiety grows the further in the future they dare to look. Finance directors in smaller business appear most concerned, with 84% reportedly worried about a brain drain effect over the next five years. This compared to 69% in larger businesses.

Under pressure, employers are counting on a range of measures to mitigate this predicted skills shortage. 45% of the employers surveyed in the research have increased training and development programmes, 32% have enhanced benefits in an effort to retain the younger baby boomers, and 16% are offering flexible/part time working to tempt their older workers to delay their departures or even better, to temporarily postpone it leaving entirely.

Whilst these methods may enhance retention rates in the short-term, eventually, employers will need to look at recruiting from the pool of available 'Generation Y' talent. Today's 'Generation Y' (early 1980's to mid 1990's) (or "Millennials") have their own well established and distinct attitudes and values when it comes to their careers. At the other end of the spectrum is Tier 2 of the problem: there is a sense (rightly or wrongly) that what worked for attracting and retaining the baby boomers, (or even arguably for 'Generation X'), won't necessarily translate well to the technically-savvy, socially well-connected and highly mobile Generation Y workers.

For example, the rapid growth of technology has seen an accompanying desire, and perhaps now an expectation, that flexible working will be available. Recent research has shown that two thirds of workers in their 20's - early 30's expect to be able to work flexibly, both in and out of the office. Do employers have the technology to support this "agile working"?

Younger workers place more emphasis than previous generations on workplace culture. Where perhaps once salary was king, it is becoming increasingly important for younger workers to work in an environment where they feel valued, and one which is in tune with their own values.

It now appears as though a 'power-shift' or change in dynamic is emerging between the expectation of employers and their Gen Y employees with degrees from prestigious universities. Managers and business owners are reporting that it's now a case of what your company can do for them, rather than what they can do for your company. Kennedy wouldn't be pleased. It's not just recruitment. What about retention?

For employers it is not just the problem of creating the right workplace conditions to attract these younger workers, which may in itself require a huge shift in culture and working practices, but also the problem of retaining them. Research has recently suggested that 79% of millennials do not feel their current employer is making the best use of their skills, and 43% believe they will have to switch jobs to acquire the skills they desire. We have previously reported that Gen Y workers will have an average of nine jobs over a 50 year career. Clearly there is no fear of moving on and starting over afresh.

Whether the myriad desires and expectations of the Gen Y workers make them the heroes or villains in the latest chapter of the All about Age story is perhaps a matter of perspective. However what is clear is that employers will need to mindful that the recruitment and retention landscape is changing fast, and that knowledge retention is becoming increasingly more challenging, and therefore more important, than ever before.

Employers face the unenviable problem of being in the squeezed middle balancing recruitment retention and knowledge transfer issues at both ends of the workplace spectrum.

This article was first published on Thompson Reuters Accleus.