In one of the biggest implementation projects currently underway in Poland we prepared a solution that supports communication of SAP ERP system with ministerial e-deklaracje system. Our application allows to read tax data generated in SAP (VAT-7, T-4R, T-11, T-40, T-8AR, PIT-8C-8S PIT, PIT-R, IFT-1R, IFT-1 ) and manage the process of acceptance of electronic signature and two-way communication with the Ministry of Finance. The solution uses XML and WebService provided by the system e-deklaracje. Communication procedures meet the requirements for confidentiality and integrity.