Methods and systems for detecting venous pulsation are provided. In one embodiment, a metric of the pulse shape of one or more plethysmographic signals is derived and the presence of venous pulsation is detected based on the metric of pulse shape. Examples, of metrics of pulse shape include a skew metric and a ratio of a minima-to-maxima time over a pulse period interval. In an exemplary embodiment, the presence of venous pulsation is detected based on a metric of the pulse shape of one or more plethysmographic signals and on a phase comparison of the plethysmographic signals.