diff --git a/changes.go b/changes.go
index d7da52d..301aafd 100644
--- a/changes.go
+++ b/changes.go
@@ -364,7 +364,7 @@ type QueryOptions struct {
 type QueryChangeOptions struct {
 	QueryOptions
 
-	// The S or start query parameter can be supplied to skip a number of changes from the list.
+	// The S or start query parameter can be supplied to skip a number of changes from the list. Only one of the two parameters can be set at a time.
 	Skip  int `url:"S,omitempty"`
 	Start int `url:"start,omitempty"`
 
@@ -391,6 +391,10 @@ type ChangeOptions struct {
 func (s *ChangesService) QueryChanges(opt *QueryChangeOptions) (*[]ChangeInfo, *Response, error) {
 	u := "changes/"
 
+	if !(opt.Skip == opt.Start || opt.Skip == 0 || opt.Start == 0) {
+		return nil, nil, fmt.Errorf("the query parameters `skip`/`S`(=%v) and `start` (=%v) are conflicting", opt.Skip, opt.Start)
+	}
+
 	u, err := addOptions(u, opt)
 	if err != nil {
 		return nil, nil, err
diff --git a/projects.go b/projects.go
index 5695c6b..1541087 100644
--- a/projects.go
+++ b/projects.go
@@ -171,7 +171,7 @@ type ProjectBaseOptions struct {
 	Limit int `url:"n,omitempty"`
 
 	// Skip the given number of branches from the beginning of the list.
-	Skip string `url:"s,omitempty"`
+	Skip string `url:"S,omitempty"`
 }
 
 // ProjectOptions specifies the parameters to the ProjectsService.ListProjects.
@@ -193,7 +193,7 @@ type ProjectOptions struct {
 	Regex string `url:"r,omitempty"`
 
 	// Skip the given number of projects from the beginning of the list.
-	Skip string `url:"S,omitempty"`
+	Start string `url:"start,omitempty"`
 
 	// Limit the results to those projects that match the specified substring.
 	Substring string `url:"m,omitempty"`
diff --git a/projects_branch.go b/projects_branch.go
index 66d8ba8..6fe3de9 100644
--- a/projects_branch.go
+++ b/projects_branch.go
@@ -32,7 +32,7 @@ type BranchOptions struct {
 	Limit int `url:"n,omitempty"`
 
 	// Skip the given number of branches from the beginning of the list.
-	Skip string `url:"s,omitempty"`
+	Skip string `url:"S,omitempty"`
 
 	// Substring limits the results to those projects that match the specified substring.
 	Substring string `url:"m,omitempty"`