An intensive use furniture concealed attachment device for securing furniture in a safe manner having a building bracket attached to the floor or wall and a tab attached to the furniture. The building bracket includes a tab flange and a pin flange. The tab is attached to the furniture in a mounting saddle formed on a mounting surface. The tab is adapted to slidingly engage the building bracket. A hole is formed in the furniture adjacent to the mounting saddle. A guide tube is disposed on the pin flange. A ball pin inserted into the hole and through the guide tube to engage the pin flange and connect the furniture to the building bracket. The tab connected to the building bracket provides support in the x, y and z axis directions.