1. Yale School of Drama (New Haven, Connecticut, USA)
> Known for its rigorous training and the success of its alumni.
2. Juilliard School (New York City, New York, USA)
> Prestigious performing arts conservatory that offers a highly selective acting program.
3. Royal Academy of Dramatic Art (London, United Kingdom)
> One of the oldest and most respected drama schools in the English-speaking world.
4. Moscow Art Theatre School (Moscow, Russia)
> Renowned for its Stanislavski method-based training and has produced many influential actors and directors.
5. Tisch School of the Arts at New York University (New York City, New York, USA)
> Offers undergraduate and graduate acting programs known for their strong curriculum.
6. California Institute of the Arts (CalArts) (Valencia, California, USA)
> Highly regarded for its innovative and interdisciplinary approach to acting training.
7. National Institute of Dramatic Art (NIDA) (Sydney, Australia)
> Australia's leading drama school with a strong reputation in the local and international industry.
8. Lee Strasberg Theatre and Film Institute (New York City, New York, USA)
> Based on the teachings of renowned acting coach Lee Strasberg and known for its focus on emotional preparation and authenticity.
9. Stella Adler Studio of Acting (New York City, New York, USA)
> Teaches the method of Strasberg's contemporary and fellow Group Theatre member, Stella Adler.
10. University of California, Los Angeles (UCLA) School of Theater, Film, and Television (Los Angeles, California, USA)
> Known for its professional acting training and the successful alumni it produces.
11. Berklee College of Music (Boston, Massachusetts, USA)
> Offers a unique program combining music and theater, with an emphasis on actor-musicians.
12. Brown University/Trinity Rep MFA in Acting (Providence, Rhode Island, USA)
> Partners with Trinity Repertory Company to offer an intensive three-year acting MFA program.
13. London Academy of Music and Dramatic Art (LAMDA) (London, United Kingdom)
> Renowned conservatoire that offers drama and musical theater training.
14. Institut del Teatre (Barcelona, Spain)
> A leading Spanish performing arts school with a strong history of producing accomplished actors.
15. National School of Drama (New Delhi, India)
> India's premiere acting school, known for its graduates who have made significant contributions to Indian theater and cinema.
It's important to note that this is a non-exhaustive list and that rankings can vary depending on factors such as the evaluation criteria, methodology, and reputation within the acting industry. Additionally, individual experiences and preferences may lead to varying opinions on the "best" acting schools.