Modern navigation heavily relies on technology. A modern ship's bridge is a high-tech centre with various equipment, such as Radar/ARPA, Automatic Identification System (AIS), Electronic Chart Display and Information Systems (ECDIS), Global Positioning System (GPS), satellite communications, and so on. The ability to operate various maritime technologies is among the most important part of navigation officers’ knowhow. However, as any technology can be an error, there will be failure happen on maritime technologies, such as navigational sensors and computer-based bridge systems. As an unsafe behaviour, over-reliance on technologies in watch keeping may have disastrous consequences. This article analysed the relationship between safe navigation of a ship and an increasing reliance placed on technology by master and officers. It identified at which stage a reliance on technology becomes an over-reliance, and the major causes of this, such as insufficient training and fatigue. Finally, it examines the consequences of an over-reliance on technology and makes some proposals on how these consequences can be prevented.