A proper diagnosis is essential for preoperative planning, allowing the surgeon to determine whether a lesion should be approached from the front, back or through a combined anterior and posterior arthroscopic approach. For a combined arthroscopic approach there are several possibilities. The main options are a proper 2-portal supine anterior arthroscopy with an auxiliary posterolateral portal, a proper 2-portal prone posterior arthroscopy with an auxiliary anterior portal or a proper 2-portal anterior scope supine followed by a proper 2-portal posterior scope prone. For most cases of combined anterior and posterior pathology it is advisable to use a proper anterior 2 portal approach supine, finish the procedure, suture the portals, apply an initial bandage, turn the patient, apply new draping and perform a proper 2 portal posterior approach. This technique is described in detail in this chapter. Indications for this combined arthroscopic approach include a combination of all symptomatic anterior and posterior pathologies. Some frequent indications are combined anterior + posterior impingement and ankle instability combined with posterior impingement. Specific indications for a combined approach are arthrolysis for arthrofibrosis and synovectomy for chondromatosis. Examples of these 4 indications are presented in this Chapter