Philippa is a Professor Emeritus at Massey University and an internationally renowned scholar of sleep and circadian rhythms.

After a PhD at Auckland University and research at Harvard Medical School and NASA Ames Research Centre, Philippa was the inaugural director of the Sleep/Wake Research Centre at Massey University.

In 2009 she was elected a Fellow of the Royal Society of New Zealand and in 2017 she was appointed an Officer of the New Zealand Order of Merit, for services to the study of sleep and fatigue.