In their current state, template-based synthetic planning tools, which rely on a classification network to predict which template can be applicable in a given context, struggle to differentiate ring-forming reactions from the multitude of other suitable reactions that can be applied to any given compound. This is due to the large number of templates available, and the relatively low frequency of ring forming reactions within the datasets (Table ). As such, in cases where a ring disconnection may be suitable or may lead to a more efficient synthetic route, the network and subsequent tree search do not often prioritize, apply, and generate synthetic routes which proceed through ring formations. To overcome this problem, the 'Ring Breaker' model can be viewed as a specialist which can be consulted at various stages of the tree search to yield routes that proceed through ring formations. In addition, the model may be used as a stand-alone tool to target a specific set of transformations. This is particularly useful when building synthetic trees interactively in a step-wise manner. In Figure we demonstrate one such use case, where the standard model fails to predict a disconnection from the bicyclic ring system. To counteract these problems, we apply the 'Ring Breaker' model. This yields a prediction from which the search for a synthetic route can be continued. In addition to using 'Ring Breaker' to kick-start the model from a point at which it becomes stuck on a ring system, the predictions can be used to supplement the standard model throughout the search for a synthetic route. Thereby, the possibilities for routes going through ring disconnections could increase, leading to more convergent synthetic routes, as opposed to a linear series of functionalisation. Incorporation of 'Ring Breaker' into general route planning tools in each of the two ways described, could help to maximise the chances of finding a more efficient route. This in turn could be used by synthetic chemists as an idea generator, to discover existing disconnections but applied in a different context. This methodology, using a domain specific model in conjunction with a standard model, can be extended to other areas of synthetic chemistry in which the data is limited and domain specific knowledge (i.e. a specialist) is required. Furthermore, the data on which the methodology relies could be augmented by integrating different data sources, in order to increase the coverage of ring forming reactions. In some cases, as that shown above the standard model fails to predict the disconnection necessary to break apart the ring system, thus it becomes stuck. Ring Breaker overcomes this bottle neck by targeting the ring system to suggest an appropriate disconnection, thus enabling the standard model to continue the retrosynthetic search to a set of building blocks. The building blocks shown are considered 'in stock', when using the ACD catalogue.