It might seem like all roads lead to ko, but what you’d really like to do is capture white’s corner…
(;SZ[19]AW[ro]AW[qp]AW[qq]AW[pr]AW[rs]AB[qk]AB[qn]AB[rn]AB[qo]AB[pp]AB[nq]AB[pq]AB[or]C[Black to play.http://gogameguru.com/]GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]RU[Japanese]KM[0.00]SO[http://gogameguru.com/]
(;B[sr];W[rq]
(;B[ps]
(;W[sn]
(;B[sp]
(;W[so]
(;B[sm];W[rp]
(;B[qr];W[rr];B[sq]C[RIGHT];W[rm];B[qm];W[rl]
(;B[ql];W[rk];B[rj]C[RIGHT])
(;B[rk]C[RIGHT]))
(;B[sq];W[qr]C[It's a seki, so white's alive.]))
(;B[qr]C[RIGHT];W[rr]
(;B[sm];W[rp];B[sq];W[rm];B[qm];W[rl]
(;B[ql];W[rk];B[rj]C[RIGHT])
(;B[rk]C[RIGHT]))
(;B[sq];W[rm];B[qm];W[rl];B[rk]LB[sm:A]LB[rp:B]C[. If black had exchanged A for B earlier, it would be slightly better now, but that's a minor detail.RIGHT]))
(;B[sq]C[];W[qr]
(;B[rp]C[RIGHT])
(;B[sm];W[rp])))
(;W[rp];B[so];W[sq];B[so]C[RIGHT]))
(;B[sm];W[sp]C[White can cause trouble some trouble with a ko like this. Try to avoid fighting ko.])
(;B[rl];W[sq])
(;B[rm];W[sq])
(;B[qr];W[rr];B[sp]C[RIGHT];W[so]
(;B[sm];W[rp];B[sq];W[rm];B[qm];W[rl]
(;B[ql];W[rk];B[rj]C[RIGHT])
(;B[rk]C[RIGHT]))
(;B[sq];W[rm];B[qm];W[rl];B[rk]LB[sm:A]LB[rp:B]C[. If black had exchanged A for B earlier, it would be slightly better now, but that's a minor detail.RIGHT])))
(;W[sp];B[sn]
(;W[rr];B[so]C[RIGHT])
(;W[sq];B[so]C[RIGHT])
(;W[so];B[sq]C[RIGHT]))
(;W[so];B[sq];W[rr];B[sn]C[RIGHT]))
(;B[so];W[sp]LB[sn:A]LB[ps:B]C[It's a ko, because A and B are miai for white. Black can do better than this.])
(;B[sp];W[sq]
(;B[so];W[ps])
(;B[ps];W[so])
(;B[qr];W[rr]
(;B[ps];W[so])
(;B[so];W[ps]))))
(;B[ps];W[so]
(;B[rr];W[qr];B[rq];W[rp]
(;B[sq];W[sr]C[It's a ko, but black can do better.])
(;B[sr];W[sq]C[It's a ko, but black can do better.]))
(;B[sr];W[sq]
(;B[rq];W[rp]C[It's a ko, but black can do better.])
(;B[rr];W[qr];B[rq];W[rp]C[It's a ko, but black can do better.]))
(;B[sq];W[sr]
(;B[rr];W[qr]C[It's a ko, but black can do better.])
(;B[qr];W[rr])
(;B[rq];W[rr];B[qr];W[rp]))
(;B[sn];W[rq]
(;B[sr];W[sq])
(;B[sq];W[sr]))
(;B[qr];W[rr]
(;B[rq];W[rp];B[sq];W[sr])
(;B[rp];W[rq])))
(;B[so];W[rq]
(;B[ps];W[sp]LB[sn:B]LB[sr:A]C[It's a ko, A and B are miai for white. Black can do better.])
(;B[rp];W[sr]
(;B[ps];W[qr])
(;B[qr];W[ps]))
(;B[sr];W[sp]LB[sn:B]LB[ps:A]C[It's a ko, A and B are miai for white. Black can do better.]))
(;B[rp];W[rq]
(;B[so];W[sr]
(;B[ps];W[qr])
(;B[qr];W[ps]))
(;B[ps];W[sp]))
(;B[qr];W[rr]
(;B[ps];W[rp];B[sq];W[sr];B[so];W[rq])
(;B[rp];W[rq]
(;B[so];W[ps])
(;B[ps];W[sp]))
(;B[rq];W[rp];B[sq];W[qs];B[so];W[sr]))
(;B[sq];W[sp];B[ps];W[sr];B[rr];W[qr];B[ss];W[qs]C[It's a ko. Black can do better.])
(;B[sp];W[rq]
(;B[sr];W[sq]
(;B[ps];W[so])
(;B[qr];W[rr];B[ps];W[so])
(;B[so];W[ps]))
(;B[ps];W[so];B[sr];W[sq]))
(;B[rq];W[rp];B[rr];W[qr];B[sr];W[ps];B[sp];W[so]C[Black has a two step ko, but this isn't a satisfactory result.])
(;B[rr];W[qr];B[sr];W[rq];B[so];W[sp]LB[sn:A]LB[ps:B]C[It's a ko. A and B are miai for white, but black can do better.]))