Sensing with quantum light: a perspective

I present my perspective on sensing with quantum light. I summarise the motivations and methodology for identifying quantum enhancements in sensing over a classical sensor. In the real world, this enhancement will be a constant factor and not increase with the size of the quantum probe as is often advertised. I use a limited survey of interferometry, microscopy and spectroscopy to extract the vital challenges that must be faced to realise tangible enhancements in sensing with quantum light.