Charlotte Edwards continued her recent good form as England claimed a 42-run, series-clinching victory over South Africa in the second women's T20 international.
Skipper Edwards batted throughout England's innings to finish 75 not out from a total of 141-3, her fourth straight half-century in international cricket this summer.
South Africa were bowled out for 99 in reply, seamer Jenny Gunn picking up 3-13 and wicketkeeper Sarah Taylor putting on a show behind the stumps with three stumpings.
Edwards and opening partner Lauren Winfield set the tone with a stand of 45 in seven overs after England, who won the first match of the three-game series at Chelmsford on Monday by nine wickets, chose to bat first.
Winfield slammed five fours in her 20-ball 22 before being stumped off Dane van Niekerk's leg-spin but Edwards received solid support from Taylor (15), Natalie Sciver (14) and Lydia Greenway (13no) to see England up to a formidable final total.
Edwards' half-century came from 45 deliveries and she went on to face 61 balls in all, hitting 11 fours.
South Africa, who had lost all nine previous completed T20 internationals between the sides, got off to a promising start in their run chase mainly thanks to the efforts of Van Niekerk (34).
From 71-2 in the 13th over, South Africa suffered a major collapse; Gunn and off-spinner Heather Knight (2-14) doing much of the damage as the tourists were all out in 18.3 overs.
England now hold an unassailable 2-0 lead in the series going into the final match at Edgbaston on Sunday.