An animal tag applicator including: a first jaw portion to engage an animal tag (or a part thereof); a second jaw portion; first and second handle portions (4, 2) pivotally connected together such that movement together of the first and second handle portions (4, 2) will cause the movement together of the first and second jaw portions (7, 3); biasing means (22, 25) to bias said jaw portions (7, 3) to an open position; said first jaw portion being caused to move under the action of the biasing means (22,25) to an open position independently of said handle portions (4, 2) but only after said animal tag (or a part thereof), has fully engaged with the animal's ear; a linkage means provided between said first handle portion and said first jaw portion which, In a first position, enables the movement of said first jaw portion towards the second jaw portion upon the movement of the handle portions (4, 2) together but, In a second position, enables said first jaw portion to be released into its open position; wherein said linkage means includes a pair of linkage members (15, 17) pivoted together and moveable from said first position to said second position once an over-centre position has been reached; and wherein a control means Is moveable with said second handle portion to be engageable with said linkage means, to move it from said first position to said over-centre position, characterized in that the biasing means (22,25) are arranged to trigger the linkage means to the second position, when the handles (4, 2) are compressed together to engage the control means with the linkage means moving the linkage means to the over-centre position, and to force back the linkage means In said first position when the handles (4, 2) are released. a first jaw portion to engage an animal tag (or a part thereof); a second jaw portion; first and second handle portions (4, 2) pivotally connected together such that movement together of the first and second handle portions (4, 2) will cause the movement together of the first and second jaw portions (7, 3); biasing means (22, 25) to bias said jaw portions (7, 3) to an open position; said first jaw portion being caused to move under the action of the biasing means (22,25) to an open position independently of said handle portions (4, 2) but only after said animal tag (or a part thereof), has fully engaged with the animal's ear; a linkage means provided between said first handle portion and said first jaw portion which, In a first position, enables the movement of said first jaw portion towards the second jaw portion upon the movement of the handle portions (4, 2) together but, In a second position, enables said first jaw portion to be released into its open position; wherein said linkage means includes a pair of linkage members (15, 17) pivoted together and moveable from said first position to said second position once an over-centre position has been reached; and wherein a control means Is moveable with said second handle portion to be engageable with said linkage means, to move it from said first position to said over-centre position, characterized in that the biasing means (22,25) are arranged to trigger the linkage means to the second position, when the handles (4, 2) are compressed together to engage the control means with the linkage means moving the linkage means to the over-centre position, and to force back the linkage means In said first position when the handles (4, 2) are released.