High-Fidelity DNA Polymerases are important for applications in which the DNA sequence needs to be correct after amplification. Fidelity is important for applications in which the DNA sequence must be correct after amplification. 

The fidelity of a polymerase refers to its ability to insert the correct base during PCR. Conversely, the rate of misincorporation is known as a polymerase's error rate. High-fidelity PCR, utilizes a DNA polymerase with a low error rate and results in a high degree of accuracy in the replication of the DNA of interest.

Different types of high-fidelity DNA polymerases are distinguished, including Pfu polymerase, a naturally faithful DNA polymerase due to its 3'-5 'exonuclease activity as well as modified DNA polymerases to obtain higher fidelity capacities.