The necessity of detecting malicious modications in hard-ware designs has led to the development of various detec-tion tools. Trojan detection approaches aim to reveal com-promised designs using several methods such as static code analysis, side-channel dynamic signal analysis, design for testing, verication, and monitoring architectures etc. This paper demonstrates new approaches for circumventing some of the latest Trojan detection techniques. We introduce and implement stealthy Trojans designs that do not violate the functional specications of the corresponding original mod-els. The designs chosen to demonstrate the effectiveness of our techniques correspond to encryption algorithms and a pseudo random number generator. The proposed Trojans are inserted into the original RTL, and decrease the overall security of the designs, minimizing detection probability by state-of-the-art static analysis tools.