Several advantages of strand displacement amplification (SDA) as an all-purpose DNA amplification reaction are due to it isothermal mechanism. The major problem of isothermal amplification mechanism is the accumulation of non-predictable byproduct especially for longer incubation time and low concentrations of initial template DNA. New theoretical strategies to tackle the difficulties regarding the specificity of the reaction are experimentally verified. Besides improving the reaction conditions, the stringency of primer hybridization can be distinctly improved by computer based sequence prediction algorithms based on the thermodynamic stability of DNA hybrid a described by the partition function of the hybridization reaction. An alternative SDA mechanism, with sequences developed by this means is also investigated.