August-Iogann-Maria Bader was a famous space explorer and progressor, whose deeds include: discovery and study of artificial satellites of Vladislava in 2121; discovery of Saraksh in 2148; compilation of the s.c. "Wanderers' Road" list (in collaboration with Leonid Gorbovsky), etc. In 2137, he was already a member of Earth's World Council and participated in the discussion of the foundlings. Bader appears in Beetle in the Anthill.
Isaac Bromberg was one of the most active anticipants of uncontrolled scientific research and information sharing in the 22nd century. He fiercely opposed the conspirative policy of COMCON-2 and, personally, Rudolf Sikorski, especially concerning the foundlings. It was he who provided Lev Abalkin all the necessary information about his origins that later led him into a deadly trap. Bromberg has also composed the s.c. "Bromberg's Memorandum", which eventually led to the discovery of the Ludens. Bromberg appears in Beetle in the Anthill.
Toivo Glumov (2167 - ?) was Maya Glumova's only son, but his father is unknown (there is a mention that his father is a hybridizator on the planet Yaila). Glumov was trained as a progressor and in 2195 investigated a series of unexplained events together with Maxim Kammerer which eventually led them to the discovery of the Ludens. During the investigation it was discovered that Glumov has a third impulse system. He became a Luden shortly after. Toyvo Glumov appears in The Time Wanderers, and briefly as a child in Beetle in the Anthill.
Maya Glumova (2141 - ?) was a historian, a space explorer and a childhood friend of Lev Abalkin. In 2161, she participated in the "Ark Project", but later applied for a job in the Museum of Extraterrestrial Cultures. In 2178, she helped Abalkin to enter the Museum, unknowingly leading him into a trap set by Rudolf Sikorski. She is also Toivo Glumov's mother. Maya Glumova appears in Beetle in the Anthill, Space Mowgli, and The Time Wanderers.
Daniel Logovenko was a Luden, who represented his race in their negotiations with humans (represented by Gennady Komov and Leonid Gorbovsky), although his main duties in the Luden community consisted of searching for and initiation of new Ludens. Logovenko had a Ph.D. in psychology and had a great reputation as a scientist. Logovenko appears in The Time Wanderers.
Saul Repnin (? - 1943) was a member of expedition that discovered Saula (named after him) in 2141 AD. Apparently, he was a human who has been shifted from one time (in this case, from mid-20th century) to another (mid-22nd century). In his "hometime" Savel Repnin was a former Red Army officer held captive in a Nazi concentration camp. Repnin was killed during an escape attempt shortly after returning in his time. Repnin appears in Escape Attempt.
Schokn-Itrch was a Golovan mostly famous for his understanding of humans and a deep bond he shared with Lev Abalkin, his long-time companion and friend. Abalkin and Schokn formed a unique human-Golovan duo and worked together on such projects as operation "Dead World" in 2163. In 2175, Schokn was promoted to the Head of the Golovan Embassy on Earth. Schokn appears in Beetle in the Anthill.
According to explicit wording of Strugatsky's (Фантасты братья Стругацкие: Ударения в словах), the correct pronunciation of the name is SchEkn (Щекн), not SchOkn (Щёкн); the name comes from щенок, puppy.
Pierre "The Kid" Semyonov (2147 - ?) was an agent of Ark Megaforms in their negotiations with Earth's progressors in 2160. Semyonov was born in 2147 on a space ship during a space trip that ended tragically for his parents. Semyonovs' spaceship "Pilgrim" was shot down by a tactical satellite that was left in the skies of Ark by the Wanderers. Both parents died; however, their son was picked up and "adopted" by the local closed civilization, fully accepting their way of existence and becoming a feral child. The Kid is the title character in Space Mowgli.
Michael Sidorov (2103 - ?), nicknamed Athos by friends, was a progressor and a biologist, who was in charge of "Ark Project" in 2160 and assisted Kammerer and Glumov in their investigation in 2195. Later during the Great Revelation he was a president of "Ural-North" sector of COMCON-2. He was also Gennady Komov's childhood friend, together with Pol Gnedyh and Alexander Kostylin. Sidorov appears in Noon: 22nd Century and Beetle in the Anthill. Also mentioned in Disquiet and Snail on the Slope (there aka Candide).
Tsuren the Truthful was a poet in the Kingdom of Arkanar. A few lines of his poems are quoted in "Hard to be a God". The most widely known is the first line of his farewell sonnet: "Like a withered leaf falling onto the soul" ("Как лист увядший падает на душу"). Many fans of Strugatskys write sonnets of their own using this line to imitate translations of the sonnet.
Jakob Vanderhoeze was a doctor and a spaceship captain, who participated in the "Ark Project" in 2160 and operation "Dead World" on Hope in 2163. Vanderhoeze is a key character in a fanfiction novel Fuckup, where he leaves the spaceship and becomes a chief inventory officer at COMCON-2.
Kornei Yashmaa (2138 - ?) was a progressor, who most famously participated on "The Giganda Project". He was also one of the "foundlings", but officially Yashmaa was a posthumous son of a couple that perished in an unsuccessful tactical exercise codenamed "Project Mirror". He was the first foundling to be informed of his true origin (in 2162) and agreed to cooperate with Earth's government. Yashmaa appears in The Kid from Hell and Beetle in the Anthill.