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Transconductance differential amplifiers directly r e f e r r e d t o g r o u n d (we will call them "pseudo-differential" structures to distinguish from the fully-differential ones) a r e not intrinsically capable of rejecting the common-mode (CM) input signal. This paper deals with the problems related to the propagation of t h e CM signal in differential circuits. A new pseudo-differential transconductor architecture with a high Common-Mode Rejection Ratio (CMRR) is proposed. The novel structure is based on a transconductor sensible only to CM signals which is added in parallel to the original one, in order to implement a feed-forward cancellation of the CM output signal current. An efficient circuital implementation of this struct u r e is presented. Comparative simulations demons t r a t e t h a t the proposed technique is competitive with the classical fully-differential one particularly a t high frequency when the CMRR rapidly degrades.