Believe it or not, Human Resources (HR) Directors and overly protective parents have a lot in common—over and above garden-variety human neuroses, that is.

Each spends a lot of time daily playing pure defense. Like a mom who stops her two-year-old from spraying a can of Raid down her throat, an HR director does her best to protect the company against risks. Top-notch, fully functioning HR directors would never hire an incompetent lunatic to run the marketing department (as opposed to a competent lunatic) or ignore implementing earthquake safety guidelines in the workplace.

Things they care about—truly, madly, and deeply—include employee performance, health and safety issues, legal compliance, lawsuits, sexual harassment, and other workplace matters. Like parents, HR directors often play a nurturing role: coming up with programs to jack up company morale, conducting training programs to enhance employee performance, etc.

But the parental role analogy can go only so far. You probably won't hear an HR director say things like: "Someday you'll thank me for this" or "I'll give you something to cry about" as she hands you your latest not-so-great performance evaluation.

^{You're getting way marked down for that 'fifties-style clothing.}

Notice all these feminine pronouns? There's a reason. These days, around three-quarters of HR honchos are women. The so-called glass ceiling is thin, if it exists at all, and HR is one of the best ways for women to come out on top in the executive suite. Many have ventured opinions about why women have been so successful in the HR jungle. Terms like "nurturing," "emotional intelligence," "intuition," "feelings" come up in discussions on this topic. But no one really knows why. Let's say it is what it is.

But for the women and the few men who become HR directors, one thing is true: Size does matter. Small, medium, and large companies each play ball with the HR department in their own ways. Here's how it goes:

In a small company, one that has fewer than 100 employees, the HR director does a bundle of stuff: collects bills, prepares invoices, enters into contracts, files papers, maintains a paper trail, deals with sexual harassment and fraud, does taxes and other accounting stuff, oversees investments, hires, fires, and manages benefits. Just look at the job as dealing with a workplace kitchen sink of duties. These kinds of companies might be restaurants, small chain stores, dry-cleaners.

One notch up are the medium-sized companies of 100 to 1,000 employees. The HR director's duties are more specialized and may involve only a few areas, such as compensation and benefits, health and safety, and professional development.

At the top of the heap are the 1,000+ employee companies. Typically here, the HR director concentrates on playing corporate defense, dealing with hiring and firing, and compensation.

This job is a play-by-the-book operation because of a thicket of laws, rules, and regulations that constrict what legally passes muster in the hiring and firing of workers. HR directors all over the world are probably getting headaches over who they can or can't fire, promote, demote, discipline, transfer, and train because of issues of ageism, racism, sexism, profiling, disability rights, and other "rights" and "isms."

But it's more than a binary world of hiring and firing in these big companies. There are retention and review duties. HR directors and their minions conduct performance reviews periodically. The inevitability of these reviews, like death and taxes, is one of the key factors why HR folks, no matter how friendly and accessible, might actually send chills up the spines of employees. Facing anonymous reviews from a clutch of supervisors, delivered by an HR person, is not a great way for an employee to spend a day.

Being lonely at the top of the corporate heap may be one of the drawbacks of being an HR director. Your workplace "friends" are, in reality, scared to death of you.

^{Although to be fair, she looks merely concerned.}

One more thing HR directors have to worry about: unions. Although unions aren't as strong as they used to be, many companies are still unionized. This means the company operates under a union contract that governs many conditions of the workplace. As a practical matter, this means HR must deal with union representatives in hiring, firing, transferring, and disciplining union workers.

This also means negotiating with shop stewards, union reps, union defense lawyers (if matters get to that point), and following contract procedures. In short, it's a lot harder to mess around with employees in a union shop.

In non-union large companies, management, including the HR director, can hire and fire at will, as long as it's for just cause and a legal reason. Of course, HR is in charge of the paperwork, such as document progressive discipline of and infractions by a worker the company wants to get rid of. But, as long as procedure is followed and the "i's" are dotted and the "t's" are crossed, things will be fine for the HR director.

But what does it take to get into HR and rise to the top? First, you need a bachelor's degree and maybe more, like an MBA or a law degree. Next, you need to be a certain type of person—one who has the interpersonal chops to deal with any kind of personality under the sun, because in the workplace you will run into a range of personality quirks, from A to Z, and beyond.

You'll have to maintain your equanimity as you lurch from meetings, job applicant interviews, health-and-safety committee presentations, phone consultations with workplace services providers, and impromptu sessions with disgruntled managers. Your days will be chock-full of people. It also helps if you organize your time well, because "multi-tasking" and juggling projects will be your life.

The bright side of being an HR director is that you can make a huge difference in promoting the health and growth of a company. You play a role in hiring the best people, and ensuring that the workplace functions well in terms of structure, safety, and organization.

The down side is participating in the ugly side of staffing. This includes fixing (or ignoring) staff shortages, settling personality clashes, announcing slashes in benefits, disciplining or firing employees, and implementing a management plan to boost employee morale, even when you think it's incredibly stupid.

But hey, the money is there and the rewards can be great.

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