Paul Callaghan was born in Wanganui, New Zealand and took his first degree in Physics at Victoria University of Wellington. After a DPhil degree at the University of Oxford, working in low temperature physics he returned to New Zealand in 1974 and took up a position at Massey University where he began researching the applications of magnetic resonance to the study of soft matter. He was made Professor of Physics in 1984, and in 2001 was appointed Alan MacDiarmid Professor of Physical Sciences at Victoria University of Wellington. In 2002 he helped establish the multi-university MacDiarmid Institute for Advanced Materials and Nanotechnology as founding director.
Paul is Past President of the Academy Council of the Royal Society of New Zealand and is currently President of the International Society of Magnetic Resonance. He has published around 240 articles in scientific journals, a 1994 book on magnetic resonance and he is a founding director and shareholder of Magritek, an company based in Wellington, which exports nuclear magnetic resonance instruments. He is a regular public speaker on science matters. In 2007 one of his radio series with Kim Hill appeared in book form, As Far as We Know: Conversations about Science, Life and the Universe and a 2009 book, "Wool to Weta: Transforming New Zealand's Culture and Economy", deals with the potential for science and technology entrepreneurialism to diversify New Zealand's economy.
In 2001 Paul became the 36th New Zealander to be made a Fellow of the Royal Society of London. He was awarded the Ampere Prize in 2004 and the Rutherford Medal in 2005. He was appointed a Principal Companion of the New Zealand Order of Merit in 2006 and in 2007 was recognised by a KEA/NZTE World Class New Zealander Award and the Sir Peter Blake Medal.