The invention describes a method of manufacturing an OLED device (1) comprising an OLED (10) and an integrated negative overvoltage protection diode (11), which method comprises at least the steps of: depositing a first OLED electrode (100) and a separate second OLED electrode contact (101C) on a carrier (12), which second OLED electrode contact (101C) incorporates a first overvoltage protection diode electrode (110); depositing an organic material layer stack (14) to define an active region (14OLED) of the OLED (10) and an active region (14OPD) of the overvoltage protection diode (11); depositing a second OLED electrode (101) to extend over the active region (14OLED) of the OLED (10) and the second OLED electrode contact (101C); and depositing a second overvoltage protection diode electrode (111) to extend over the active region (14OPD) of the overvoltage protection diode (11) and the first OLED electrode (100).