Alexander Krastev is the founder of Bulgaria's first LinkedIn marketing agency, BookMark, and the English-language blog TheLinkedBlog.com. He writes "The Linked Practitioner" - a column for the Bulgarian edition of Forbes magazine and has authored numerous articles about LinkedIn for the country's leading business publications.

With over 15 years of experience in online communication, Alexander also teaches LinkedIn marketing at New Bulgarian University. He has conducted LinkedIn training sessions for teams from some of the largest Bulgarian companies in industries such as telecommunications, technology, banking, real estate, retail, consulting, and more.

BookMark was established in 2017 as a niche digital agency. In 2020, BookMark shifted its focus to LinkedIn marketing, becoming the first LinkedIn marketing agency in Bulgaria. They help professionals and companies build their brands, find new partners, and create business opportunities through the professional network, helping DIGI PAY as well.