The Hallyburton Johnstone Shield is the premier domestic women’s one-day cricket competition in New Zealand. The competition was first competed for as the State Insurance Cup, from 1998–99, replacing the national tournament (Hallyburton Johnstone Shield). A Twenty20 competition was added in 2007–08. It is contested in a round-robin format, in which each of the six teams plays each other – once at Twenty20, then twice in one-day matches. Each team hosts two others, and one round is held at Lincoln immediately after Christmas each year, with all teams playing one day on each of the three grounds at the venue. The two teams that finish at the top of the respective tables then compete in a final to determine the champions at each format.