The phrase "tight deadlines" refers to a situation where there is very little time available to complete a task or project. It implies that the schedule is extremely tight and there is not much room for error, delays or setbacks. People working under such conditions often face high levels of stress and pressure as they try to meet their goals within the given timeframe. The phrase can also be used more generally to describe any situation where deadlines are very close together or closely spaced, making it difficult to manage multiple tasks at once.