diff --git a/Cargo.lock b/Cargo.lock
index b108c89f..b95c0e67 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -594,7 +594,7 @@ dependencies = [
  "der",
  "elliptic-curve",
  "rfc6979",
- "signature",
+ "signature 1.6.4",
 ]
 
 [[package]]
@@ -603,7 +603,7 @@ version = "1.5.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "91cff35c70bba8a626e3185d8cd48cc11b5437e1a5bcd15b9b5fa3c64b6dfee7"
 dependencies = [
- "signature",
+ "signature 1.6.4",
 ]
 
 [[package]]
@@ -2141,6 +2141,12 @@ dependencies = [
  "rand_core 0.6.4",
 ]
 
+[[package]]
+name = "signature"
+version = "2.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8fe458c98333f9c8152221191a77e2a44e8325d0193484af2e9421a53019e57d"
+
 [[package]]
 name = "slab"
 version = "0.4.8"
@@ -2432,7 +2438,7 @@ dependencies = [
  "generic-array",
  "p256",
  "rand 0.7.3",
- "signature",
+ "signature 2.0.0",
  "tink-core",
  "tink-proto",
 ]
diff --git a/signature/Cargo.toml b/signature/Cargo.toml
index bcb3d747..bc978689 100644
--- a/signature/Cargo.toml
+++ b/signature/Cargo.toml
@@ -18,6 +18,6 @@ generic-array = "^0.14.6"
 p256 = "^0.11.1"
 # `rand` version must match that required by `ed25519-dalek`.
 rand = "^0.7"
-signature = "^1.6"
+signature = "^2.0"
 tink-core = "^0.2"
 tink-proto = "^0.2"