|Abstract:||Efficient monitoring of parametric properties, in spite of increasingly growing interest thanks to applications such as testing and security, imposes a highly non-trivial challenge on monitoring approaches due to the potentially huge number of parameter instances. A few solutions have been proposed, but most of them compromise their expressiveness for performance or vice versa. In this paper, we propose a generic, in terms of specification formalisms, yet efficient, solution to monitoring parametric specifications. Our approach is based on a general semantics for slicing parametric traces and makes use of knowledge about the property to monitor. The needed knowledge is not specific to the underlying formalism and can be easily computed when generating monitoring code from the property. An extensive evaluation shows that the monitoring code generated by our algorithm is still faster than other state-of-art techniques optimized for particular logics or properties.