@wikipedia

 A value of of required discount rate which nullifies the project's NPV  to nullify the expected NPV of the Investment Project:

\mbox{NPV} = \sum_{i=0}^n \frac{R_i}{(1+\mbox{IRR})^i} = 0

...

The usual practise is to give preferences to the investment projects Investment Projects with higher IRR and make a direct comparison of IRR against the Weighted Average Cost of Capital (WACC).

The corporate investment policy usually dictates that:

• Investment Projects with IRR < WACC should be rejected
  
  
• Investment Projects with higher IRR should have a financing priority over the Investment Projects with lower IRR

See also

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Economics / Investment / Financial Investment / Cash DiscountFinancial Investment Metrics

[ Financial Investment Project ]

[ Weighted Average Cost of Capital (WACC) ] [ Cash Discount ] [ Net Present Value (NPV) ] 

[ Modified Internal Rate of Return (MIRR) ]