The Grand Slam in shinty consists of a club winning all four major trophies for which it is eligible.
The MacAulay Cup was first played for in 1947, and this can be gauged as the beginning of the Grand Slam era.
Although both Ballachulish and Lovat have won the Glasgow Celtic Society and MacTavish Cups respectively, this was outside a Grand Slam season (Balla's win was before the advent of the MacAulay Cup) although Lovat won the first Grand Slam two years later, in 1953.
Kinlochshiel achieved this in 2021 when they added the Camanachd and MacTavish to their 2016 & 2018 MacAulay and 2017 Premiership wins.
Due to the district division of shinty in Scotland into North and South, a "National Slam" has only been achieved by Lovat who have won all five major trophies - the Camanachd, the MacAulay, the MacTavish and the MacGillvray League (North One), when this functioned as the tier one league as well as the Glasgow Celtic Society as an invited club.