Malformations of cortical development (MCDs) consist of a group of brain developmental anomalies. These disorders were originally named according to their gross anatomical appearances: polymicrogyria (PMG), schizencephaly, lissencephaly (LIS), hemimegalencephaly, grey matter heterotopia and focal cortical dysplasia (FCD). This chapter considers surgical treatment of refractory epilepsy due to various types of MCD. Tumours such as dysembryoplastic neuroepithelial tumour and ganglioglioma were sometimes labelled as ‘developmental’ and were categorized under MCD in some classification schemes. The most common and distinct disorders are considered separately, highlighting surgical results. A particular emphasis is placed on FCD, which is the most common type of MCD diagnosed in surgical series. The chapter discusses advancement in various presurgical assessments, including imaging technique and EEG monitoring.