Thank the last few years of economic turmoil for this small favor: The predicted talent shortage driven by retiring baby boomers has yet to happen. Although the first boomers started turning 65 in 2011, many have opted to stay in the workforce rather than tap their shrunken nest eggs. Meanwhile, financial necessity or sheer boredom is luring many older workers back out of retirement—not just in the United States, but all over the world, says Pete Sanborn, global practice leader and president of talent consulting, Aon Hewitt.

As a result, when Aon Hewitt experts talk about hiring challenges, they aren't talking about a massive global brain drain. They're referring to something smaller, yet no less difficult to manage: a high level of competition for employees with key skills, and the resulting need to be ever more strategic about hiring decisions.

What's created this mismatch between needed skills and available talent? Within the United States, it's about the highly paid but relatively lower-skilled manufacturing jobs that powered the U.S. economy in the 20th century being replaced by highly demanding technical jobs in the service and technology sectors, says Brian Dunn, CEO, global compensation and talent, Aon Hewitt.

Internationally, Sanborn points out, emerging economies are creating increased competition as they attract highly skilled technical and engineering talent. Developed markets' ability to draw technical talent has weakened as there are now excellent opportunities—for those with key skills—in countries such as India and China.

Either way, companies are having a harder time finding the skills, education and experience they need when and where they need them most. And at a time when Hewitt's 2011-2012 Salary Increase Survey suggests most organizations must keep a tight rein on human resources (HR) costs, the process of matching the right candidate to the right job is more challenging than ever. So here, we offer advice based on some of the key hiring challenges facing global businesses.

Challenge 1: Tight Budget

The problem: Your budget for salaries and pay increases is limited.

The solution: Become a "destination employer" with a reputation for helping employees build a long-term career.

A decade ago, employers could fill job openings by promising a fat paycheck. Today, companies can't necessarily up the cash ante—but that's actually good news because today's employee wants more than just money.

"You need a strong perception that your company is a good place to develop a career, not just a steppingstone," says Sanborn. That means offering ongoing training and career development, innovative compensation and benefits plans, coaching and mentoring, and other ways beyond salary to show employees that they're valued. Leading companies are investing in assessments and targeted development to demonstrate their commitment to supporting employee career development, which is the No. 1 driver of engagement globally, he says.

"As organizations become leaner, they've cut out a lot of steps in the career ladder, and it's harder to learn from someone with more experience when they aren't there to learn from," Dunn points out. "If your employees can't figure out how to climb your career ladder, they have to go elsewhere. … You have to create a framework where people are going to get the opportunities they need."

Challenge 2: Build or Buy

The problem: Your company has no local or internal candidate with the appropriate skills or experience for a critical position.

The solutions: Promote someone local from within, transfer a qualified employee from another location, or hire a local external candidate—preferably in that order.

If growing internal talent is your top priority, you may occasionally have to fill an open position with an employee who isn't quite ready for the role, says Sanborn. If you have no appropriate local candidate, you may need to consider relocating an employee from elsewhere in the organization, especially for a short-term assignment that offers career-building experience.