diff --git a/src/PackageUrl.cs b/src/PackageUrl.cs
index 3d20bd1..b86abf9 100644
--- a/src/PackageUrl.cs
+++ b/src/PackageUrl.cs
@@ -46,6 +46,7 @@ public sealed class PackageURL
         /// The url encoding of /.
         /// </summary>
         private const string EncodedSlash = "%2F";
+        private const string EncodedColon = "%3A";
 
         private static readonly Regex s_typePattern = new Regex("^[a-zA-Z][a-zA-Z0-9.+-]+$", RegexOptions.Compiled);
 
@@ -146,27 +147,31 @@ public override string ToString()
             }
             if (Name != null)
             {
-                purl.Append(Name);
+                string encodedName = WebUtility.UrlEncode(Name).Replace(EncodedColon, ":");
+                purl.Append(encodedName);
             }
             if (Version != null)
             {
-                purl.Append('@').Append(Version);
+                string encodedVersion = WebUtility.UrlEncode(Version).Replace(EncodedColon, ":");
+                purl.Append('@').Append(encodedVersion);
             }
             if (Qualifiers != null && Qualifiers.Count > 0)
             {
                 purl.Append("?");
                 foreach (var pair in Qualifiers)
                 {
+                    string encodedValue = WebUtility.UrlEncode(pair.Value).Replace(EncodedSlash, "/");
                     purl.Append(pair.Key.ToLower());
                     purl.Append('=');
-                    purl.Append(pair.Value);
+                    purl.Append(encodedValue);
                     purl.Append('&');
                 }
                 purl.Remove(purl.Length - 1, 1);
             }
             if (Subpath != null)
             {
-                purl.Append("#").Append(Subpath);
+                string encodedSubpath = WebUtility.UrlEncode(Subpath).Replace(EncodedSlash, "/").Replace(EncodedColon, ":");
+                purl.Append("#").Append(encodedSubpath);
             }
             return purl.ToString();
         }
@@ -205,7 +210,7 @@ private void Parse(string purl)
             if (remainder.Contains("#"))
             { // subpath is optional - check for existence
                 int index = remainder.LastIndexOf("#");
-                Subpath = ValidateSubpath(remainder.Substring(index + 1));
+                Subpath = ValidateSubpath(WebUtility.UrlDecode(remainder.Substring(index + 1)));
                 remainder = remainder.Substring(0, index);
             }
 
@@ -219,7 +224,7 @@ private void Parse(string purl)
             if (remainder.Contains("@"))
             { // version is optional - check for existence
                 int index = remainder.LastIndexOf("@");
-                Version = remainder.Substring(index + 1);
+                Version = WebUtility.UrlDecode(remainder.Substring(index + 1));
                 remainder = remainder.Substring(0, index);
             }
 
@@ -235,7 +240,7 @@ private void Parse(string purl)
             }
 
             Type = ValidateType(firstPartArray[0]);
-            Name = ValidateName(firstPartArray[firstPartArray.Length - 1]);
+            Name = ValidateName(WebUtility.UrlDecode(firstPartArray[firstPartArray.Length - 1]));
 
             // Test for namespaces
             if (firstPartArray.Length > 2)
@@ -248,7 +253,7 @@ private void Parse(string purl)
                 }
                 @namespace += firstPartArray[i];
 
-                Namespace = ValidateNamespace(@namespace);
+                Namespace = ValidateNamespace(WebUtility.UrlDecode(@namespace));
             }
         }
 
@@ -269,8 +274,8 @@ private string ValidateNamespace(string @namespace)
             }
             return Type switch
             {
-                "bitbucket" or "github" or "pypi" or "gitlab" => WebUtility.UrlDecode(@namespace.ToLower()),
-                _ => WebUtility.UrlDecode(@namespace)
+                "bitbucket" or "github" or "pypi" or "gitlab" => @namespace.ToLower(),
+                _ => @namespace
             };
         }
 
@@ -297,7 +302,7 @@ private static SortedDictionary<string, string> ValidateQualifiers(string qualif
                 if (pair.Contains("="))
                 {
                     string[] kvpair = pair.Split('=');
-                    list.Add(kvpair[0], kvpair[1]);
+                    list.Add(kvpair[0], WebUtility.UrlDecode(kvpair[1]));
                 }
             }
             return list;
diff --git a/tests/PackageUrl.Tests.cs b/tests/PackageUrl.Tests.cs
index 3a84673..9f0a7a5 100644
--- a/tests/PackageUrl.Tests.cs
+++ b/tests/PackageUrl.Tests.cs
@@ -43,7 +43,6 @@ public void TestConstructorParsing(PurlTestData data)
 
             PackageURL purl = new PackageURL(data.Purl);
             Assert.Equal(data.CanonicalPurl, purl.ToString());
-
             Assert.Equal("pkg", purl.Scheme);
             Assert.Equal(data.Type, purl.Type);
             Assert.Equal(data.Namespace, purl.Namespace);
diff --git a/tests/TestAssets/test-suite-data.json b/tests/TestAssets/test-suite-data.json
index 42182f1..ab7f709 100644
--- a/tests/TestAssets/test-suite-data.json
+++ b/tests/TestAssets/test-suite-data.json
@@ -385,5 +385,65 @@
     "qualifiers": null,
     "subpath": null,
     "is_invalid": false
+  },
+  {
+    "description": "valid nuget purl containing a + in version",
+    "purl": "pkg:nuget/Microsoft.NET.Sdk.MacCatalyst.Manifest-6.0.400@15.4.471%2Bsha.9382aa8e0",
+    "canonical_purl": "pkg:nuget/Microsoft.NET.Sdk.MacCatalyst.Manifest-6.0.400@15.4.471%2Bsha.9382aa8e0",
+    "type": "nuget",
+    "name": "Microsoft.NET.Sdk.MacCatalyst.Manifest-6.0.400",
+    "version": "15.4.471+sha.9382aa8e0",
+    "qualifiers": null,
+    "namespace": null,
+    "subpath": null,
+    "is_invalid": false
+  },
+  {
+    "description": "valid maven purl containing a plus in qualifier",
+    "purl": "pkg:maven/mygroup/myartifact@1.0.0Final?mykey=my%2Bvalue",
+    "canonical_purl": "pkg:maven/mygroup/myartifact@1.0.0Final?mykey=my%2Bvalue",
+    "type": "maven",
+    "namespace": "mygroup",
+    "name": "myartifact",
+    "version": "1.0.0Final",
+    "qualifiers": { "mykey": "my+value" },
+    "subpath": null,
+    "is_invalid": false
+  },
+  {
+    "description": "valid go purl with plus in subpath",
+    "purl": "pkg:GOLANG/google.golang.org/genproto#/google%2Bapis/api/annotations/",
+    "canonical_purl": "pkg:golang/google.golang.org/genproto#google%2Bapis/api/annotations",
+    "type": "golang",
+    "namespace": "google.golang.org",
+    "name": "genproto",
+    "version": null,
+    "qualifiers": null,
+    "subpath": "google+apis/api/annotations",
+    "is_invalid": false
+  },
+  {
+    "description": "valid go purl with colon unencoded in name, version and subpath",
+    "purl": "pkg:GOLANG/google.golang.org/gen:proto@abc:dedf#/google:apis/api/annotations/",
+    "canonical_purl": "pkg:golang/google.golang.org/gen:proto@abc:dedf#google:apis/api/annotations",
+    "type": "golang",
+    "namespace": "google.golang.org",
+    "name": "gen:proto",
+    "version": "abc:dedf",
+    "qualifiers": null,
+    "subpath": "google:apis/api/annotations",
+    "is_invalid": false
+  },
+  {
+    "description": "valid go purl with slash in name, namespace, version and qualifier",
+    "purl": "pkg:GOLANG/google.golang.org/repo/gen%2Fproto@abc%2Fdedf?repository_url=go.googlesource.com/go",
+    "canonical_purl": "pkg:golang/google.golang.org/repo/gen%2Fproto@abc%2Fdedf?repository_url=go.googlesource.com/go",
+    "type": "golang",
+    "namespace": "google.golang.org/repo",
+    "name": "gen/proto",
+    "version": "abc/dedf",
+    "qualifiers": { "repository_url": "go.googlesource.com/go" },
+    "subpath": null,
+    "is_invalid": false
   }
 ]