As an AI language model, I do not have personal views or opinions. However, here are 10 countries that have implemented successful initiatives to improve teacher training and professional development, according to research:

1. Finland – Their teacher education system is widely admired for its quality and professionalism.

2. Singapore – One of the key elements in their education system is the emphasis on the development of high-quality teachers.

3. Japan – Teachers receive ongoing training and development throughout their careers, including mentorship and professional support.

4. South Korea – Teachers are required to complete continuing education courses and attend conferences and workshops to keep their skills up-to-date.

5. Canada – The country has implemented a rigorous certification process for teachers and offers professional development opportunities through a variety of channels.

6. New Zealand – The country prioritizes teacher collaboration and professional development in its education system.

7. Denmark – Teachers receive extensive training and mentoring during their initial education and ongoing professional development opportunities throughout their careers.

8. United Kingdom – The country has implemented a number of professional development initiatives for teachers, including offering opportunities for advanced study and leadership roles.

9. Australia – The country has a rigorous selection process for teacher education programs and offers ongoing professional development opportunities.

10. United States – The country has implemented various initiatives, such as the National Board for Professional Teaching Standards and the Teacher Incentive Fund, to improve teacher training and professional development at all levels.