One of the pitfalls that nearly every collector will encounter sooner or later, are stamps and covers that are not what they appear to be. They may be complete forgeries, stamps that have been skillfully repaired to appear superb, or they may be genuine stamps that have been altered in some way to enhance their value. Learning how to spot these items is an important skill for every advanced collector to learn. The pages below cover some of the types of alterations commonly encountered and what to look for in detecting them.