Because happiness is not only good for the worker, it's good for business. Costs fall and profits rise when employees are happy.
The business case for happiness is increasingly accepted by senior management following ground-breaking research; primarily in the United States, a market more generally known for relentless focus on shareholder value.
Los Angeles-based Korn Ferry, world leaders in executive search, recently published a series of articles showing that happy employees are 31% more productive than those who are unhappy while happy staff generate 37% more sales.
What's more, employees who are happy are 40% more promotable. They are better able to take on the next challenge than colleagues who are miserable in their jobs.
The percentages apply overall - from the shop floor to the corporate suite - and come from an authoritative source; Shawn Achor, a former Harvard professor, now CEO of the GoodThink Inc. consultancy.
To further substantiate the case, US observers point to the marketplace success of techno companies like Google that go to great lengths to make their workers happy.
Google is the world's second most valuable company by market capitalisation. Its market cap of $391 billion is second only to that of oil giant Exxon Mobil.
Another example of a multi-national firm that openly embraces happiness is Coca-Cola (slogan: Open Happiness). Its market cap tops $180 billion.
To build a happy team, Google provides on-site day-care, gives workers meals, does their dry cleaning, lays on oil changes for their cars and other perks.
Some big employers provide on-site gyms, hair salons and other services. The aim is higher staff retention, but the essential building block is employee happiness at the workplace.
US business consultants and industrial psychologists are currently revisiting and redefining happiness.
It is seen as immunisation against poor motivation when the job threatens to get on top of you.
'Happiness injections' may take the form of support services, perks or efforts to make the work more fulfilling and satisfying.
It sounds manipulative, but the effects are beneficial. You feel good about yourself because you are so obviously valued.
Leaders are also alert to the happiness challenge. Senior executives increasingly join their people in celebrating relatively small wins. It cements team spirit and lifts morale.
The happiness reappraisal focuses attention on the journey rather than the destination. Traditionally, staff members worked seriously hard on the job and had fun after hours, at the weekend or in retirement.
Today, you are encouraged to be happy in your work and have fun making your work-a-day contribution.
Get it right and productivity rises, absenteeism falls, recruitment costs are contained, the ideas flow, innovation accelerates and profits climb.
Business is discovering you really can smile all the way to the bank. But first you have to spread some happiness around.
