Continuous scaling in the technology feature size and hence the supply voltage, has directed analog designers to change the signal representation from voltage domain to current domain. That is why the high performance current-mode building blocks have received a great deal of interest. The current-mode is better than the voltage-mode in such aspects like: lower voltage supplies, lower power consumption, wider dynamic range and higher bandwidth. The current-mode circuits offer higher frequency capabilities than corresponding voltage-mode circuits due to the constant bandwidth irrespective of the closed loop gain. The objective of this thesis is to introduce differential and single ended high performance CMOS analog mixed voltage-current-mode building blocks suitable for analog signal processing applications. Moreover, a fair comparison criterion is adopted throughout the thesis while designing all the old and new circuits.