Incisional hernias develop through weaknesses in the abdominal wall that result from prior abdominal surgeries. Risk factors include surgical techniques like midline incisions and poor suture methods, as well as patient characteristics such as age, obesity, and smoking. Treatment involves either open suture repair for small hernias or open/laparoscopic mesh repair for larger hernias, with mesh repair having a lower recurrence rate but higher risk of infection. Proper surgical technique and modification of patient risk factors can help reduce hernia development and recurrence.