Two youth dance companies taking full advantage of the Fringe Festival's capacity to act as a testing ground for touring grit are Burklyn Youth Ballet from the United States, and the Cape Youth Dance Company from South Africa.
Burklyn Youth Ballet is spawned from a summer school held in Vermont for students from all over the United States. .
Sticking strictly to the traditions of classical ballet, the cast - mainly females aged 13 to 21 - perform throughout on pointe. A strong supporting role is provided by the company's one male, Alexander Lodigiani, who recently turned professional and is now in the corps of Nevada Ballet Theatre.
His grace and strength are the perfect counterpoint for the willowy, almost watery, movements of one of the company's other principal dancers, an ultra-thin Gretta Murray. Together the pair lend a delicate pace to the Et in terra pax section of Vivaldi's Gloria.
For other sections we are treated to splashes of rich pinks and purples as different groups of dancers interpret Vivaldi's score and the choreography of the late Dennis Spaight (of Ballet Oregon).
The second half is a ballet based on Hans Christian Andersen's tale of the Snow Queen. The cool, blonde Gretta Murray is ideal as the icy queen attempting to use her magic to compete with true love and defeat individual choice and free will. But most watchable, with a refreshingly lyrical performance and strong dramatic presence is Rachel Dreskin as Gerda who temporarily loses her friend Kay to the avaricious Queen.
A very different company, which should be on any list of "must sees" at the festival is Cape Youth Dance. Here is a group of youngsters who give full vent to their natural musicality, fluid athleticism and sense of humour.
Established in 1995, they are on their second visit to Edinburgh with a programme that shows growing confidence and maturity, and taps into a universal youth culture as well as that of contemporary South Africa.
It helps that the company of 14, which is white bar one, now has a strong black male lead in Wesley Davids and that it uses indigenous music by, for example, the Soweto String Quartet and Hugh Masekela.
In the first of an hour-long series of short pieces, the dancers come in, en masse, in Fight, Flight or Freeze and just don't let up the pace of wide kicks and turns interlaced with taut portrayals of conflict.
In The Byrds and the Bees, by contrast, they reveal their ability to joke without being too slapstick. In stripy costumes Davids, along with Jaco van Rensburg, the other male dancer, perform the role of bumbling bees pollinating a strong-minded line-up of female flowers.
The tone becomes sterner again in One flew over...", with music by Stockhausen, as the female cast, clad in identical white slips, hint at the fine line between conformity and madness. And with In Your Face, a piece on youth unemployment, the dancers evoke the hopelessness, frustration and aching disappointment of being told by an answering machine that there are no messages.
The occasional phases here of almost acrobatic dancing appear slightlyincongruous, but in 4SSQ, by the company's artistic director Debbie Turner, there is little to fault in the choreography, which allows the dancers to exploit the entire stage with expert glissades, turns and leaps interspersed with energetic running.
When some indolent-looking schoolboys come out of the theatre chatting about their intentions of coming back, and one expresses his new-found ambition to be a dancer, you know the show is a winner.
Burklyn Youth Ballet, August 8-15, Venue 82, Southside, 117 Nicolson Street, tel: 0131 667 2212. Cape Youth Dance Company, August 10-22 (not 16), Venue 128, Youth International at St Oswald's, tel: 0131 229 5562 Kay Smith