diff --git a/internal/lsp/server.go b/internal/lsp/server.go
index b8b09525..30c74178 100644
--- a/internal/lsp/server.go
+++ b/internal/lsp/server.go
@@ -57,6 +57,7 @@ func (s *server) Initialize(ctx context.Context, params *protocol.InitializePara
 			DefinitionProvider:              true,
 			DocumentFormattingProvider:      true,
 			DocumentRangeFormattingProvider: true,
+			HoverProvider:                   true,
 			SignatureHelpProvider: protocol.SignatureHelpOptions{
 				TriggerCharacters: []string{"(", ","},
 			},
@@ -184,8 +185,24 @@ func (s *server) CompletionResolve(context.Context, *protocol.CompletionItem) (*
 	return nil, notImplemented("CompletionResolve")
 }
 
-func (s *server) Hover(context.Context, *protocol.TextDocumentPositionParams) (*protocol.Hover, error) {
-	return nil, notImplemented("Hover")
+func (s *server) Hover(ctx context.Context, params *protocol.TextDocumentPositionParams) (*protocol.Hover, error) {
+	f := s.view.GetFile(source.URI(params.TextDocument.URI))
+	tok, err := f.GetToken()
+	if err != nil {
+		return nil, err
+	}
+	pos := fromProtocolPosition(tok, params.Position)
+	contents, rng, err := source.Hover(ctx, f, pos)
+	if err != nil {
+		return nil, err
+	}
+	return &protocol.Hover{
+		Contents: protocol.MarkupContent{
+			Kind:  protocol.Markdown,
+			Value: contents,
+		},
+		Range: toProtocolRange(tok, rng),
+	}, nil
 }
 
 func (s *server) SignatureHelp(ctx context.Context, params *protocol.TextDocumentPositionParams) (*protocol.SignatureHelp, error) {
diff --git a/internal/lsp/source/completion.go b/internal/lsp/source/completion.go
index 5f8e3d80..5524de21 100644
--- a/internal/lsp/source/completion.go
+++ b/internal/lsp/source/completion.go
@@ -101,8 +101,8 @@ func completions(file *ast.File, pos token.Pos, fset *token.FileSet, pkg *types.
 	}
 
 	// The position is within a composite literal.
-	if items, ok := complit(path, pos, pkg, info, found); ok {
-		return items, "", nil
+	if items, prefix, ok := complit(path, pos, pkg, info, found); ok {
+		return items, prefix, nil
 	}
 	switch n := path[0].(type) {
 	case *ast.Ident:
@@ -250,7 +250,7 @@ func lexical(path []ast.Node, pos token.Pos, pkg *types.Package, info *types.Inf
 
 // complit finds completions for field names inside a composite literal.
 // It reports whether the node was handled as part of a composite literal.
-func complit(path []ast.Node, pos token.Pos, pkg *types.Package, info *types.Info, found finder) (items []CompletionItem, ok bool) {
+func complit(path []ast.Node, pos token.Pos, pkg *types.Package, info *types.Info, found finder) (items []CompletionItem, prefix string, ok bool) {
 	var lit *ast.CompositeLit
 
 	// First, determine if the pos is within a composite literal.
@@ -286,6 +286,8 @@ func complit(path []ast.Node, pos token.Pos, pkg *types.Package, info *types.Inf
 			}
 		}
 	case *ast.Ident:
+		prefix = n.Name[:pos-n.Pos()]
+
 		// If the enclosing node is an identifier, it can either be an identifier that is
 		// part of a composite literal (e.g. &x{fo<>}), or it can be an identifier that is
 		// part of a key-value expression, which is part of a composite literal (e.g. &x{foo: ba<>).
@@ -311,7 +313,7 @@ func complit(path []ast.Node, pos token.Pos, pkg *types.Package, info *types.Inf
 	}
 	// We are not in a composite literal.
 	if lit == nil {
-		return nil, false
+		return nil, prefix, false
 	}
 	// Mark fields of the composite literal that have already been set,
 	// except for the current field.
@@ -351,10 +353,10 @@ func complit(path []ast.Node, pos token.Pos, pkg *types.Package, info *types.Inf
 			if !hasKeys && structPkg == pkg {
 				items = append(items, lexical(path, pos, pkg, info, found)...)
 			}
-			return items, true
+			return items, prefix, true
 		}
 	}
-	return items, false
+	return items, prefix, false
 }
 
 // formatCompletion creates a completion item for a given types.Object.
diff --git a/internal/lsp/source/definition.go b/internal/lsp/source/definition.go
index b4f05f48..7990325e 100644
--- a/internal/lsp/source/definition.go
+++ b/internal/lsp/source/definition.go
@@ -30,7 +30,7 @@ func Definition(ctx context.Context, f *File, pos token.Pos) (Range, error) {
 		return Range{}, err
 	}
 	if i.ident == nil {
-		return Range{}, fmt.Errorf("definition was not a valid identifier")
+		return Range{}, fmt.Errorf("not a valid identifier")
 	}
 	obj := pkg.TypesInfo.ObjectOf(i.ident)
 	if obj == nil {
diff --git a/internal/lsp/source/hover.go b/internal/lsp/source/hover.go
new file mode 100644
index 00000000..2c04a884
--- /dev/null
+++ b/internal/lsp/source/hover.go
@@ -0,0 +1,50 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package source
+
+import (
+	"context"
+	"fmt"
+	"go/token"
+	"go/types"
+)
+
+func Hover(ctx context.Context, f *File, pos token.Pos) (string, Range, error) {
+	fAST, err := f.GetAST()
+	if err != nil {
+		return "", Range{}, err
+	}
+	pkg, err := f.GetPackage()
+	if err != nil {
+		return "", Range{}, err
+	}
+	i, err := findIdentifier(fAST, pos)
+	if err != nil {
+		return "", Range{}, err
+	}
+	if i.ident == nil {
+		return "", Range{}, fmt.Errorf("not a valid identifier")
+	}
+	obj := pkg.TypesInfo.ObjectOf(i.ident)
+	if obj == nil {
+		return "", Range{}, fmt.Errorf("no object")
+	}
+	if i.wasEmbeddedField {
+		// the original position was on the embedded field declaration
+		// so we try to dig out the type and jump to that instead
+		if v, ok := obj.(*types.Var); ok {
+			if n, ok := v.Type().(*types.Named); ok {
+				obj = n.Obj()
+			}
+		}
+	}
+	// TODO(rstambler): Add documentation and improve quality of object string.
+	content := types.ObjectString(obj, qualifier(fAST, pkg.Types, pkg.TypesInfo))
+	markdown := "```go\n" + content + "\n```"
+	return markdown, Range{
+		Start: i.ident.Pos(),
+		End:   i.ident.End(),
+	}, nil
+}