By the year 2020, a nationwide shortage of up to 500,000 trained nurses could mean that hundreds of thousands of patients will receive less attention and substandard treatment. Just as alarming, fewer nurses are choosing to teach the next generation of professionals, resulting in tens of thousands of applicants being turned away from the nation's nursing schools. NOW on PBS takes a hard look at the strains this crisis is placing on the entire medical system, as well as innovative efforts to reverse the trend.