At the end of the Latvian state Institute of physical culture in the 50s years of the last century, Grigolyunovich was sent to the Daugavpils pedagogical Institute. Parallel teaching became player-coach of the local team Khimik. There he noticed another legendary Latvian coach, Michael Amalin, Sigismunda invited to the national team of Latvia.

At the end of the 60s, Grigolyunovich joined the coaching staff of the leader of the Latvian volleyball — "Radio". In 1970 was the head coach of the team. Then worked in tandem with Gennady Parsinen, a "Radio technician" repeatedly became the prize-winner of USSR championship and also a three-time winner of the Cup winners ' Cup (1974, 1975, 1977).

Coaching talent Grigolyunovich was appreciated and he was appointed the second coach of the USSR national team and also head coach of the student team of the USSR. At the head of these two teams Sigismund was in for four years. In 1979, the Latvian specialist was sent to raise volleyball in Madagascar. Almost from nothing he was able to create an efficient national team, which in 1981 took 3-th place in the Cup of Africa.

Back home, the Grigolyunovich received an offer to lead the main women's team of Latvia — "Aurora". It was almost the most successful years of the Latvian team in the Championships of the USSR.

After the restoration of independence of Latvia Sigismund continued to work in women's volleyball, leading the different teams ("Aurora", "Income", "Jauniba", LOU/ESTs) and the national team, which reached the final tournament of the European championship.

In 2007, Sigismund the Grigolyunovich back in men's volleyball, becoming the second coach of the team "Ozolnieki/priors". On the eve of his 80th birthday he was not afraid to lead "priors", and last season worked with a team of "Marupe".

Merit for the national volleyball in 2015 by the decree of the President of Latvia Sigismund the Grigolyunovich awarded the Cross of Recognition of the fourth degree.