Career Abroad

Hi, I’m from Brazil and I have got 10 years of experience in Procurement. I want to carry on with my career abroad though. To achieve this goal I’m improving my English. Since I have never worked overseas I have some doubts: what are the International Certificates most demanded by the Companies? What are the degrees mostly accepeted to work in countries like England, Australia, Canada and USA in the Procurement area? I am looking forward to receive any information that can help me with these concerns. Best Regards.