SKA is an international project to build the largest and most sensitive radio telescope ever conceived, being the greatest data research public project, once complete. It will be composed of thousands of antennas on Africa and Australia and it will generate a copious data flux (around 1TB/s). A worldwide distributed network of SKA Regional Centres (SRCs) will provide access to the SKA data, to the analysis tools and processing power. The SRCs will be at the core of the exploitation of SKA data, being the place where the science will be done. We have long been aware of the need to face the challenge of handling SKA data to extract scientific knowledge, and our compromise is that this is done not only in an efficient way, but following the Scientific Method (hence in a reproducible way). Thus we are particularly engaged in the challenge of ensuring that Big Data science becomes Open Science in the SRCs, becoming the SRCs a reference not only in science and technology but also in Scientific Methodology. IAA-CSIC has started prototyping a SRC that will be fully aligned with the Open Science Principles. Astronomy has a long-standing tradition on Open Access through the International Virtual Observatory Alliance (IVOA) but there are new solutions emerging from other fields, involving using e-Science technologies to enhance scientific collaboration, ensuring transparency, opening data collection and methods, or encouraging Open Science.