Glen has frequently undertaken massive, innovative international projects - she was the first foreign woman to direct at the 14,000-seat Epidaurus amphitheatre in Greece, where she directed Prometheus in Greek. (This production also toured Greece and Canada).

In 1979 she founded the Chung Ying Theatre Company in Hong Kong and opened the Queen Elizabeth Stadium with a musical version of her adaptation of Animal Farm in English and Cantonese. Later she helped steer the company to independent status with its own Board of Governors. She directed many English and Cantonese-speaking productions integrating both British and Chinese cultures. Productions played major venues in Hong Kong and toured throughout South East Asia.

In 1986 she was invited to Japan to create a popular performing 'house-style' and direct Rhyming Theatre Company's annual Shakespeare productions. (With Japanese actors, directed in Japanese) She adapted Japanese translations, incorporated facets of Japanese and English culture, introduced actor-musicians and made full use of flexible space. Much Ado About Nothing (1986) Comedy 0f Errors (also toured Japan 1987) Measure For Measure (1988) Merchant 0f Venice (Best production award 1990) As You Like It (1992) Macbeth (1994)

Other productions in Japan include Educating Rita - Theatre Project Tokyo Benisan Pit.
Merchant of Venice, Blood Brothers (premiere and three subsequent revivals) Shochiku Company Ltd. Sunshine Theatre, Aoyama Theatre (Tokyo) Nagoya Theatre (Nagoya), Minamiza Theatre (Kyoto) - (all in Japanese).

Glen has also directed for Vienna's English Theatre - Midsummer Night's Dream, As You Like It, The Dresser and Skylight.
Her most recent production for this theatre was directing her own adaptation of A Portrait of Dorian Gray.

She directed Gilbert and Sullivan's HMS Pinafore which was the first in-house production for the 1,800 seat theatre at the Mondavi Centre, Davis, California, U.S.A.

She directed a new production of Blood Brothers for Fuji Television Network for the Aoyama Theatre, Tokyo and Osaka.

Most recently in 2005 she directed a massive sell-out success with 'Grand Hotel' for Fuji Television Network and is now working on a new musical - 'Titanic The Musical' again for Fuji Television Network