Performing attention-demanding tasks concurrently with timing distorts estimated durations. In studies reviewed, consistent interference between timing in the range of seconds and concurrent memory search was found, but no interference with visual search, switching or activation from long-term memory. We underscore the similarity between this pattern and results observed in research on complex span, a measure of working memory capacity. According to an executive attention view of working memory capacity, high-working memory capacity individuals are better at maintaining goals, a useful ability in timing. Another group of studies shows that expectancy interfered with timing, similarly to memory processing. Implicit timing is the source of interference in those studies, an influence that must be considered in timing studies on interference effects.