In this paper, Peter Hamilton surveys the caselaw on causation in slipping cases. He illustrates how courts use ‘probabilistic reasoning’ to fill gaps in evidence about the timing of spills before an incident and how this is often used by plaintiffs to establish liability, even though there may be no evidence about when the spill occurred. The paper covers the leading decision of Strong v Woolworths, but explores its origins and how it has been applied more recently, ending with tips for practitioners on evidence gathering.