Sock (Make 2)
CO 90 sts, and distribute as follows over 4 needles: 23 sts on first and fourth needles, 22 sts on second and third needles. Place marker and join to begin working in the round, being careful not to twist.
The point at which the join happens will be the center back of the sock.
Work in 1x1 rib for 15 rounds.
IMPORTANT NOTE: Rows (rounds) will be counted from this point.

Work in stockinette st for 92 rounds.
Set-up Rnd: K22, place marker, k46, place marker, k22.
Shaping Rnd: K to 2 sts before first marker, k2tog, k to second marker, slip marker, k2tog, k to end of round.
[Work 3 rnds even. Work Shaping Round.] 3 times. 82 sts rem. (Rnd 106 just worked.)
Work 38 rnds even. (Round 144 just worked.)
[Work Shaping Rnd. Work 1 round even.] 13 times. 56 sts rem. (Rnd 170 just worked.)
Work Shaping Rnd once more. 54 sts rem.
Work 68 rounds even. (Rnd 239 just worked.)

Shape foot
Place first 14 and last 13 sts of round onto one dpn: the heel flap wil be worked on these 27 sts. Place rem 27 sts on a st holder or piece of waste yarn.
Work in stockinette st until heel flap measures 2.5 inches, ending with a RS row.

Work Short-Row Heel Shaping
Row 1 [WS]: P15, p2tog, p1, turn.
Row 2 [RS]: Sl1 kwise, k5, k2tog, k1, turn.
Row 3 [WS]: Sl1 pwise, p6, p2tog, p1, turn.
Row 4 [RS]: Sl1 kwise, k7, k2tog, k1, turn.
Row 5 [WS]: Sl1 pwise, p8, p2tog, turn.
Row 6 [RS]: Sl1 kwise, k9, k2tog, k1, turn.
Row 7 [WS]: Sl1 pwise, p10, p2tog, turn.
Row 8 [RS]: Sl1 kwise, k11, k2tog, turn.
Row 9 [WS]: Sl 1 pwise, p12, p2tog, turn.
Row 10 [RS]: Sl1 kwise, k13, k2tog, turn.
Row 11 [WS]: Sl1 pwise, p14, p2tog. 16 sts rem.
Turn work so RS is facing.
Pick up and k 15 sts along left side of heel flap. Using a second dpn, work across 27 sts on front of foot. Using a third dpn, pick up and k 15 sts along rem side of heel flap, and k 8 sts from heel flap. (Sts should now be distributed as follows: 23 sts on first and third needles, 27 sts on second needle. 73 sts. NOTE: Foot will be worked using four needles instead of five.)

Shape Instep
Rnd 1: K to last 3 sts on first needle, k2tog, k1, k across all sts on second needle, k first st on third needle, k2tog, k to end.
Rnd 2: K all sts.
Work these 2 rnds 8 times more. 55 sts rem.
Next Rnd: K to last 3 sts on first needle, k2tog, k1, k all sts on second and third needles. 54 sts. (13 sts on first needle, 27 sts on second needle, 14 sts on third needle.)
Work even until work from base of heel measures 3 inches less than total length of foot.

Shape Toe
Next Rnd: K to last 3 sts of first needle, k2tog, k1, k first st of second needle, k2tog, k to last 3 sts of second needle, k2tog, k1, k first st of third needle, k2tog, k to end.
Next Rnd: K all sts.
Work these 2 rnds 5 times more. 30 sts rem.
Work first rnd only, 4 times. 14 sts rem.
Work sts on first needle only then break yarn, leaving a 12 inch tail.
Transfer sts on third needle to first needle: 7 sts on first needle and 7 sts on second needle.
Using Kitchener stitch, graft sts on first needle to sts on second needle.