Grammar goofs, mechanical missteps, punctuation problems, and spelling slips-ups undercut individual professionalism and organizational credibility. The ability to write clearly and correctly is key to career success. A whopping 86 percent of HR professionals consider poorly written resumes and cover letters to be deal breakers for job applicants. Fully 51 percent of recruiters at major U.S. corporations take writing skills into account when hiring. Considering that two-thirds of salaried employees at large companies are required to write on the job, now is the time to get a grip on grammar.