Summary: How to repoint a brick wall, remove old mortar and repoint the brickwork.
Over a period of years, a wall can lose some or all of the mortar holding the bricks together. This will make the wall unattractive, and after too long, will become penetrated by damp. Maintaining the mortar is important in protecting the structure of the wall. The mortar that holds the bricks is also known as pointing.
If the damage is concentrated in just one area, then it is possible to repoint just that area. However, the newly pointed patch will stand out clearly, so you may wish to take the time to re-point the entire wall.