I submitted through online system and received and email from the HR manager in Barcelona. The entire process of application submission was conducted in English. My resume, cover letter and the job description was in English. The email correspondence from HR was al in English. The job did not list any language requirements. During the interview, I picked up the phone and the entire interview was in Spanish. I had prepared mostly for an English interview. As you can imagnie, total curve ball!!! I had emailed back saying, that I had not anticipated and would love to re-interview, after having the opportunity to study up a bit further. I speak Spanish relatively well, though conducting over Skype, and without preparing, it heightened my nerves and I performed poorly. Airbnb allows you to review their interviewing process afterwards, and I specficially said that this was a lack of information for the interviewee and job description should say "must speak spanish". A few weeks later I noticed they had changed the description on their website.