A new survey by The Creative Group polled advertising and marketing executives on the greatest challenge of writing job descriptions. Twenty-eight percent of respondents said identifying the necessary soft skills for the job is the top challenge; 24 percent claimed it is most difficult to accurately describe job duties.

Writing job descriptions is a high-stakes task. "A well-written job description can mean the difference between a trickle or a flurry of qualified applicants," says Diane Domeyer, executive director of The Creative Group. "Conversely, a poorly written job description can significantly expand the quantity of unqualified applicants."

Here are five guidelines for writing effective job descriptions every time.

Look ahead. Consider how the skill set necessary to do the job could change in the future, and how the person in the role will support your organization's long-term objectives.

Prioritize. Don't post a laundry list of every little duty the job could entail. Have high-performing employees in the same role help you highlight its most strategic responsibilities in the job description.

Must-haves must not exceed five or six essential skills or qualities. Listing 15 "must-haves" could turn away would-be candidates with unexpectedly valuable talents.

Let some personality shine through. Although the description should be clear and concise, it also should give candidates a feel for your organization's culture. If appropriate, explain what it's like to work at your organization. Consider turning to internal editors or your creative team for help with this.

Always be improving. Posting a job opening is a great opportunity to dust off the existing job description. Think about how you might define it in a way that attracts talented workers who will expand the role's value.