--- a/net/minecraft/world/entity/decoration/EntityLeash.java
+++ b/net/minecraft/world/entity/decoration/EntityLeash.java
@@ -25,6 +25,12 @@
 import net.minecraft.world.phys.AxisAlignedBB;
 import net.minecraft.world.phys.Vec3D;
 
+// CraftBukkit start
+import net.minecraft.network.protocol.game.PacketPlayOutAttachEntity;
+import net.minecraft.server.level.EntityPlayer;
+import org.bukkit.craftbukkit.event.CraftEventFactory;
+// CraftBukkit end
+
 public class EntityLeash extends EntityHanging {
 
     public static final double OFFSET_Y = 0.375D;
@@ -96,22 +102,42 @@
             while (iterator.hasNext()) {
                 entityinsentient = (EntityInsentient) iterator.next();
                 if (entityinsentient.getLeashHolder() == entityhuman) {
+                    // CraftBukkit start
+                    if (CraftEventFactory.callPlayerLeashEntityEvent(entityinsentient, this, entityhuman).isCancelled()) {
+                        ((EntityPlayer) entityhuman).connection.sendPacket(new PacketPlayOutAttachEntity(entityinsentient, entityinsentient.getLeashHolder()));
+                        continue;
+                    }
+                    // CraftBukkit end
                     entityinsentient.setLeashHolder(this, true);
                     flag = true;
                 }
             }
 
             if (!flag) {
-                this.die();
-                if (entityhuman.getAbilities().instabuild) {
+                // CraftBukkit start - Move below
+                // this.die();
+                boolean die = true;
+                // CraftBukkit end
+                if (true || entityhuman.getAbilities().instabuild) { // CraftBukkit - Process for non-creative as well
                     iterator = list.iterator();
 
                     while (iterator.hasNext()) {
                         entityinsentient = (EntityInsentient) iterator.next();
                         if (entityinsentient.isLeashed() && entityinsentient.getLeashHolder() == this) {
-                            entityinsentient.unleash(true, false);
+                            // CraftBukkit start
+                            if (CraftEventFactory.callPlayerUnleashEntityEvent(entityinsentient, entityhuman).isCancelled()) {
+                                die = false;
+                                continue;
+                            }
+                            entityinsentient.unleash(true, !entityhuman.getAbilities().instabuild); // false -> survival mode boolean
+                            // CraftBukkit end
                         }
                     }
+                    // CraftBukkit start
+                    if (die) {
+                        this.die();
+                    }
+                    // CraftBukkit end
                 }
             }
 
